Compressible non-fibrous adjuncts

Abstract

Stapling assemblies for use with surgical staplers are provided. In one exemplary embodiment, the stapling assembly includes a cartridge having a plurality of staples disposed therein and a non-fibrous adjunct formed from at least one fused bioabsorbable polymer and configured to be releasably retained on the cartridge. Adjunct systems for use with surgical staplers are also provided. Surgical end effectors for use with the stapling assemblies are also provided. Methods for manufacturing and using the stapling assemblies are also provided.

Description

[0001] Cross Reference to Related Applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 900,708, filed September 16, 2019, entitled “Bioabsorbable Resin for Additive Manufacturing,” U.S. Provisional Patent Application No. 62 / 913,227, filed October 10, 2019, entitled “Bioabsorbable Resin for Additive Manufacturing,” and U.S. Provisional Patent Application No. 63 / 053,863, filed July 20, 2020, entitled “Compressible 3D Printed Scaffolds,” the disclosures of which are incorporated by reference herein in their entireties. TECHNICAL FIELD

[0003] Compressible non-fibrous adjuncts and methods of making and using the same are provided. BACKGROUND

[0004] Surgical staplers are used in surgical procedures to close openings in tissue, blood vessels, conduits, shunts, or other objects or body portions involved in a particular procedure. These openings can be naturally occurring, such as passageways in blood vessels or internal organs like the stomach, or they can be created by the surgeon during the surgical procedure, such as by puncturing tissue or blood vessels to create a bypass or anastomosis, or by cutting tissue during a stapling procedure.

[0005] Some surgical staplers require the surgeon to select an appropriate staple with an appropriate staple height for the tissue being stapled. For example, the surgeon can select a long staple for thick tissue and a short staple for thin tissue. However, in some cases, the tissue being stapled does not have a consistent thickness, so the staple cannot achieve the desired fired configuration at every staple site. As a result, the desired seal is not formed at or near all of the staple sites, allowing blood, air, gastrointestinal fluids, and other fluids to seep through the unsealed sites.

[0006] Additionally, staples, as well as other objects and materials that can be implanted in connection with procedures similar to stapling, often lack some of the properties of the tissue in which they are implanted. For example, staples, as well as other objects and materials, can lack the natural pliability of the tissue in which they are implanted, and thus cannot withstand the internal pressure differentials at the implant site. This can result in undesirable tearing of the tissue at or near the staple site, and thus leakage.

[0007] Accordingly, there remains a need for improved instruments and methods for addressing the current problems with surgical staplers. SUMMARY

[0008] Also provided are stapling assemblies for use with surgical staplers. In one exemplary embodiment, a stapling assembly includes a non-fibrous adjunct and a cartridge having a plurality of staples disposed therein, the plurality of staples configured to be deployed into tissue, and the non-fibrous adjunct formed of at least one fused bioabsorbable polymer and configured to be releasably retained on the cartridge such that the adjunct is attachable to tissue by the plurality of staples in the cartridge. The adjunct has a first end, a second end, and a longitudinal axis extending therebetween, wherein the adjunct includes at least two different compression zones, each compression zone defined by a different grid structure of repeating geometric cells formed by interconnected struts. Each grid structure has a different compression strength such that the adjunct has a variable compression strength along a transverse direction relative to the longitudinal axis.

[0009] The compression zones can have a variety of configurations. For example, in some embodiments, the at least two different compression zones can include a first compression zone having a first compression strength and a second compression zone having a second compression strength that is less than the first compression strength. In other embodiments, the at least two different compression zones can include a first compression zone having a first compression strength and a second compression zone having a second compression strength that is less than the first compression strength. In certain embodiments, the cartridge can include a slot extending into and along at least a portion of the cartridge and can be configured to receive a cutting element, wherein the second compression zone can be configured to at least partially overlap the slot when the adjunct is attached to the cartridge. In some embodiments, at least a portion of the first compression zone can be positioned around a perimeter of the adjunct. In other embodiments, the at least two different compression zones can include a third compression zone having a third compression strength that is less than the second compression strength. In some embodiments, at least a portion of the third compression zone can be positioned around a perimeter of the adjunct. In certain embodiments, the cartridge can include a slot extending into and along at least a portion of the cartridge and can be configured to receive a cutting element, wherein the third compression zone can be configured to at least partially align with the slot when the adjunct is attached to the cartridge.

[0010] The adjunct can have a variety of configurations. For example, in some embodiments, the adjunct can have a tissue-contacting surface and a cartridge-contacting surface opposite the tissue-contacting surface, the cartridge-contacting surface having a plurality of attachment features extending outwardly therefrom and configured to extend into recesses defined within the cartridge. In other embodiments, the plurality of attachment features can be arranged in a repeating pattern across the cartridge-contacting surface, the repeating pattern can be configured to substantially overlap a repeating pattern of the recesses defined within the cartridge.

[0011] In another example embodiment, a stapling assembly for use with a surgical stapler includes a non-fibrous adjunct and a cartridge having a plurality of staples disposed therein, the plurality of staples being configured to be deployed into tissue, and the non-fibrous adjunct being formed of at least one fused bioabsorbable polymer and configured to be releasably retained on the cartridge such that the adjunct is attachable to tissue by the plurality of staples in the cartridge. The adjunct includes a first compression zone having a first compression strength and a second compression zone having a second compression strength different from the first compression strength, the first compression zone being defined by a first lattice structure formed of a first plurality of repeating unit cells, the second compression zone being defined by a second lattice structure formed of a second plurality of repeating unit cells, the second plurality of repeating unit cells being different from the first plurality of repeating unit cells. The first compression zone and the second compression zone are positioned adjacent to each other and laterally offset from each other relative to a longitudinal axis of the adjunct.

[0012] The repeating unit cells can have various configurations. For example, in some embodiments, the first repeating unit cells can be a first triply periodic minimal surface structure, and the second plurality of repeating unit cells can be a second triply periodic minimal surface structure. In other embodiments, the first triply periodic minimal surface structure can vary in at least one of a height and a wall thickness compared to a height and a wall thickness of the second triply periodic minimal surface structure.

[0013] The adjunct can have various configurations. For example, in some embodiments, the adjunct can include a third compression zone having a third compression strength that can be different from the first compression strength and the second compression strength, the third compression zone being defined by a third lattice structure formed of a third plurality of repeating unit cells, wherein the third compression zone can be laterally offset from the first compression zone and the second compression zone. In other embodiments, the first plurality of repeating unit cells can be a first triply periodic minimal surface structure, the second plurality of repeating unit cells can be a second triply periodic minimal surface structure, and the third plurality of repeating unit cells can be a third triply periodic minimal surface structure. In some embodiments, the first triply periodic minimal surface structure, the second triply periodic minimal surface structure, and the third triply periodic minimal surface structure can vary in at least one of a height and a wall thickness relative to each other. In certain embodiments, the first triply periodic minimal surface structure, the second triply periodic minimal surface structure, and the third triply periodic minimal surface structure can be Schwarz-P structures. In other embodiments, the first compression zone can be an innermost compression zone of the adjunct, and the third compression zone can be an outermost compression zone of the adjunct. In other embodiments, the third compression strength can be less than the first compression strength and the second compression strength. In certain embodiments, the cartridge can include a slot extending into and along at least a portion of the cartridge and can be configured to receive a cutting element, wherein the first compression zone can be a proximal-most compression zone relative to the slot. Attached Figure Description

[0014] The invention will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0015] Figure 1 A perspective view of an exemplary embodiment of a conventional surgical suturing and cutting instrument;

[0016] Figure 2A To and Figure 1 A top view of a staple cartridge used in conjunction with surgical suturing and cutting instruments;

[0017] Figure 2B for Figure 2A Side view of the staple cartridge;

[0018] Figure 2C for Figure 2A A perspective view of a portion of the tissue contact surface of the staple cartridge;

[0019] Figure 3 It can be set to Figure 4 A side view of the staple cartridge of the surgical cartridge assembly in an unfired (pre-deployed) configuration with staples in the cartridge.

[0020] Figure 4 for Figure 1 A perspective view of the scalpel and firing lever (“E-beam”) of a surgical suturing and cutting instrument;

[0021] Figure 5 for Figure 1 A perspective view of the wedge-shaped slider of the staple cartridge for surgical suturing and cutting instruments;

[0022] Figure 6A A longitudinal cross-sectional view of an exemplary embodiment of a surgical cartridge assembly having compressible non-fibrous appendages attached to the top or platform surface of the staple cartridge;

[0023] Figure 6B This is a longitudinal sectional view of a surgical end effector having an anvil pivotally connected to a narrow pin channel and Figure 6A The surgical chamber assembly is set within and connected to the slender screw channel, and the figure shows the anvil in a closed position with no tissue between the anvil and the appendage;

[0024] Figure 7 To show Figures 6A-6B A partial schematic diagram of an appendage under organizational deployment conditions;

[0025] Figure 8 is a perspective view of another exemplary embodiment of a compressible non-fibrous appendage;

[0026] Figure 8B forFigure 8A side view of the adjunct of FIG. 8A;

[0027] Figure 8C top view of the adjunct of FIG. 8A; Figure 8A

[0028] Figure 8D cross-sectional view of the adjunct of FIG. 8A taken at line 8D-8D; Figure 8C

[0029] Figure 8E cross-sectional view of the adjunct of FIG. 8A taken at line 8E-8E; Figure 8C

[0030] Figure 8F enlarged view of a portion of the adjunct of FIG. 8A taken at 8F; Figure 8C

[0031] Figure 8G partial schematic view showing the adjunct of FIG. 8A in an organized deployed state; Figure 8A

[0032] Figure 9A side view of a single cell of the adjunct of FIG. 8A; Figure 8A

[0033] Figure 9B perspective view of a single cell of FIG. 8A; Figure 9A

[0034] Figure 10A schematic view of an exemplary cell in a pre-compressed state;

[0035] Figure 10B Figure 10A schematic view of a cell of FIG. 8A in a first compressed state;

[0036] Figure 10C Figure 10A schematic view of a cell of FIG. 8A in a second compressed state;

[0037] Figure 10D Figure 10A schematic view of a cell of FIG. 8A in a dense state;

[0038] Figure 11 Figures 10A-10D schematic view of the relationship between the state of a cell of FIG. 8A and the resulting stress-strain curve of the compressible non-fibrous adjunct;

[0039] Figure 12A

[0040] Figure 12B ​​​​​​​​​​​​top view of an exemplary embodiment of a compressible non-fibrous adjunct formed from repeating unit cells of another embodiment of a modified Schwarz-P structure;

[0041] Figure 12C top view of an exemplary embodiment of a compressible non-fibrous adjunct formed from repeating unit cells of another embodiment of a modified Schwarz-P structure;

[0042] Figure 12D top view of an exemplary embodiment of a compressible non-fibrous adjunct formed from repeating unit cells of another embodiment of a modified Schwarz-P structure;

[0043] FIG. 13 is a perspective view of another exemplary embodiment of a single unit cell;

[0044] Figure 13B top view of an exemplary embodiment of a compressible non-fibrous adjunct formed from repeating unit cells of Figure 13A ;

[0045] Figure 14A perspective view of another exemplary embodiment of a single unit cell;

[0046] Figure 14B top view of an exemplary embodiment of a compressible non-fibrous adjunct formed from repeating unit cells of Figure 14A ;

[0047] Figure 15A perspective view of another exemplary embodiment of a single unit cell;

[0048] Figure 15B top view of an exemplary embodiment of a compressible non-fibrous adjunct formed from repeating unit cells of Figure 15A ;

[0049] Figure 16A perspective view of another exemplary embodiment of a single unit cell;

[0050] Figure 16B top view of an exemplary embodiment of a compressible non-fibrous adjunct formed from repeating unit cells of Figure 16A ;

[0051] Figure 17A perspective view of another exemplary embodiment of a compressible non-fibrous adjunct;

[0052] Figure 17B cross-sectional view of the adjunct of Figure 17A taken at line 17B-17B;

[0053] Figure 17C cross-sectional view of the adjunct of Figure 17AA cross-sectional view of the appendage taken at point 17C-17C along the line;

[0054] Figure 18 A perspective view of another exemplary embodiment of a compressible non-fibrous appendage disposed on a staple cartridge;

[0055] Figure 19A A perspective view of another exemplary embodiment of a compressible non-fibrous appendage having a channel attachment;

[0056] Figure 19B for Figure 19A A cross-sectional view of the appendages taken at line 19B-19B;

[0057] Figure 20 A partial perspective view of another exemplary embodiment of a compressible non-fibrous appendage having a channel attachment;

[0058] Figure 21 A partial perspective view of another exemplary embodiment of a compressible non-fibrous appendage having a channel attachment;

[0059] Figure 22A The following is a partially exploded perspective view of an exemplary embodiment of a suture assembly having compressible non-fibrous appendages releasably held on a staple cartridge, each compressible non-fibrous appendage having a corresponding edge attachment feature.

[0060] Figure 22B An enlarged cross-sectional view taken at line 22B to 22B of a portion of the suture assembly shows the two edge attachment features prior to joining;

[0061] Figure 22C for Figure 22B A cross-sectional view of a portion of the suture assembly, showing the two edge attachment features joined together;

[0062] Figure 23A This is a perspective view of another exemplary embodiment of a suture assembly having compressible non-fibrous appendages releasably held on a staple cartridge, each compressible non-fibrous appendage having a corresponding edge attachment feature, the figure showing the joined edge attachment features;

[0063] Figure 23B for Figure 23B A magnified view of a portion of the suture assembly;

[0064] Figure 24 A perspective view of another exemplary embodiment of a staple cartridge having end attachment features;

[0065] Figure 25 A perspective view of another exemplary embodiment of a staple cartridge having end attachment features;

[0066] Figure 26A exploded view of another example embodiment of a stapling assembly having a staple cartridge and a compressible non-fiber adjunct, wherein the attachment features are releasably retained on the compressible non-fiber adjunct;

[0067] Figure 26B is a cross-sectional view taken at line 26B-26B of the stapling assembly of Figure 26A

[0068] Figure 26C is a cross-sectional view taken at line 26C-26C of the stapling assembly of Figure 26A

[0069] Figure 27 is a partial cross-sectional view of another example embodiment of a stapling assembly having a compressible non-fiber adjunct releasably retained on a staple cartridge;

[0070] Figure 28A is a partial cross-sectional view of another example embodiment of a stapling assembly having a compressible non-fiber adjunct releasably retained on a staple cartridge;

[0071] Figure 28B is a partial schematic view showing the adjunct of Figure 28A

[0072] Figure 29 is a partial cross-sectional view of another example embodiment of a stapling assembly having a compressible non-fiber adjunct releasably retained on a staple cartridge;

[0073] Figure 30A is a perspective view of another example embodiment of a compressible non-fiber adjunct;

[0074] Figure 30B is a front plan view of the adjunct of Figure 30A

[0075] Figure 31A is a perspective view of one embodiment of a compressible non-fiber adjunct;

[0076] Figure 31B is a perspective view of a single cell of the adjunct of Figure 31A

[0077] is a side view of a cell of Figure 31C Figure 31B is an alternative side view of a cell of

[0078] Figure 31D Figures 31B-31C is an alternative side view of a cell of

[0079] ​​​​​​Figure 32A Perspective view of another exemplary embodiment of a compressible non-fibrous adjunct;

[0080] Figure 32B Perspective view of a single cell of the adjunct of Figure 32A

[0081] Figure 32C Side view of the cell of Figure 32B

[0082] Figure 32D Cross-sectional top view of the cell of Figures 32B-32C along line 32D-32D of Figure 32C

[0083] Figure 33A Perspective view of another exemplary embodiment of a compressible non-fibrous adjunct;

[0084] Figure 33B Perspective view of a single cell of the adjunct of Figure 33A

[0085] Figure 33C Side view of the cell of Figure 33B

[0086] Figure 33D Top view of the cell of Figures 33B-33C along line 33D-33D of Figure 33C

[0087] Figure 33E Alternative side view of the cell of Figures 33B-33C

[0088] Figure 34A Perspective view of another exemplary embodiment of a compressible non-fibrous adjunct;

[0089] Figure 34B Perspective view of a single cell of the adjunct of Figure 34A

[0090] Figure 34C Side view of the cell of Figure 34B

[0091] Figure 34D Top view of the cell of Figures 34B-34C

[0092] Figure 34E Alternative side view of the cell of Figures 34B-34C

[0093] Figure 35 Perspective view of another exemplary embodiment of a compressible non-fibrous adjunct; ​​​​​​​​​​​

[0094] Figure 36 perspective view of another example implementation of a unit cell;

[0095] Figure 37A partial exploded perspective view of another example implementation of a stapling assembly having a staple cartridge and a compressible non-fiber adjunct;

[0096] Figure 37B is a cross-sectional view taken at line 37B-37B of a portion of the stapling assembly of Figure 37A

[0097] Figure 38A is a schematic view of a portion of the stapling assembly of Figure 37B

[0098] Figure 38B is a partial schematic view showing the adjunct of Figure 37A in a tissue-deployed condition;

[0099] Figure 39A is an exploded view of an example implementation of a stapling assembly having a staple cartridge and an adjunct, wherein only a second outer layer of the adjunct is shown;

[0100] Figure 39B is a front view of the stapling assembly of Figure 39A

[0101] Figure 40 is a perspective view of another example implementation of a stapling assembly having a compressible non-fiber adjunct releasably retained on a staple cartridge;

[0102] Figure 41A is a perspective view of another example implementation of a compressible non-fiber adjunct;

[0103] Figure 41B is a cross-sectional view of a portion of the adjunct of Figure 41A taken at line 41B-41B and releasably retained on a staple cartridge;

[0104] Figure 41C is a cross-sectional view of a portion of the adjunct of Figure 41A taken at line 41C-41C and releasably retained on a staple cartridge;

[0105] Figure 42A is a perspective view of another example implementation of a compressible non-fiber adjunct;

[0106] Figure 42B is a partial schematic view showing the adjunct of Figure 42A in a tissue-deployed condition;

[0107] ​​​Figure 43A Perspective view of another exemplary embodiment of a compressible non-fibrous adjunct;

[0108] Figure 43B Cross-sectional view of an adjunct of Figure 43A taken at line 43B-43B;

[0109] Figure 44A Cross-sectional view of another exemplary embodiment of a compressible non-fibrous adjunct, showing only a portion of the adjunct being releasably held on a staple cartridge;

[0110] Figure 44B Partial schematic view showing tissue clamped between an anvil and Figure 44A a portion of an adjunct of wherein staples are partially deployed through the adjunct from a staple cartridge;

[0111] Figure 44C Partial schematic view showing an adjunct of Figure 44A in a tissue-deployed condition;

[0112] Figure 45A Partial exploded perspective view of another exemplary embodiment of a stapling assembly having a compressible non-fibrous adjunct releasably held on a staple cartridge;

[0113] Figure 45B Top view of a portion of a stapling assembly of Figure 45A ;

[0114] Figure 45C Cross-sectional view of a stapling assembly of Figure 45B taken at line 45C-45C;

[0115] Figure 46A Perspective view of another exemplary embodiment of a portion of a stapling assembly having a compressible non-fibrous adjunct releasably held on a staple cartridge;

[0116] Figure 46B Top view of a portion of a stapling assembly of Figure 46A ;

[0117] Figure 47A Cross-sectional front view of an exemplary embodiment of a surgical end effector having an anvil and a stapling assembly with a compressible non-fibrous adjunct releasably held on a staple cartridge, showing the surgical end effector in a closed position with no tissue positioned between the anvil and the stapling assembly;

[0118] Figure 47B Cross-sectional front view of a surgical end effector of Figure 47A showing tissue clamped between the anvil and the stapling assembly and stapled to the compressible non-fibrous adjunct;

[0119] Figure 47C for Figure 47A A cross-sectional front view of only the stitched components;

[0120] Figure 48A A cross-sectional front view of another exemplary embodiment of a surgical end effector having an anvil and a suture assembly having a compressible non-fibrous appendage releasably held on a staple cartridge. The figure illustrates a surgical end effector in a closed position with no tissue positioning between the anvil and the suture assembly.

[0121] Figure 48B for Figure 48A A cross-sectional front view of a surgical end effector showing tissue held between the anvil and the suture assembly and sutured to a compressible non-fibrous appendage;

[0122] Figure 48C for Figure 48A A front view of the cross-section of only the stitched components;

[0123] Figure 49 A perspective view of another exemplary embodiment of a compressible non-fibrous appendage;

[0124] Figure 50A A side view of an exemplary embodiment of a surgical end effector having an anvil and a suture assembly having a compressible non-fibrous appendage releasably held on a staple cartridge. The figure illustrates a surgical end effector in a closed position with no tissue positioning between the anvil and the suture assembly.

[0125] Figure 50B for Figure 50A A side view of the surgical end effector, showing tissue held between the anvil and the suture assembly;

[0126] Figure 50C for Figure 50A A side view of only the stitched components;

[0127] Figure 51A A cross-sectional front view of another exemplary embodiment of a surgical end effector having an anvil and a suture assembly having a compressible non-fibrous appendage releasably held on a staple cartridge. The figure illustrates a surgical end effector in a closed position with no tissue positioning between the anvil and the suture assembly.

[0128] Figure 51B for Figure 51A A front view of a section of only compressible non-fibrous appendages;

[0129] Figure 52Aa cross-sectional front view of another exemplary embodiment of a surgical end effector having an anvil and a stapling assembly having a compressible non-fiber adjunct releasably held on a cartridge, illustrating the surgical end effector in a closed position with no tissue positioned between the anvil and the stapling assembly;

[0130] Figure 52B a cross-sectional front view of a portion of the stapling assembly of Figure 52A

[0131] Figure 53 a cross-sectional view of a portion of another exemplary embodiment of a compressible non-fiber adjunct releasably held on a cartridge;

[0132] Figure 54 a cross-sectional view of a portion of another exemplary embodiment of a compressible non-fiber adjunct releasably held on a cartridge, illustrating only three staples from three staple rows of the cartridge;

[0133] Figure 55 a graphical representation of stress-strain curves for the adjunct of Figure 54

[0134] Figure 56 a graph illustrating stress-strain curves for the exemplary compressible non-fiber adjuncts of Examples 9 and 10 (Adjunct 1);

[0135] Figure 57 a graph illustrating stress-strain curves for the exemplary compressible non-fiber adjuncts of Examples 9 and 10 (Adjuncts 2-5); and

[0136] Figure 58 a graph illustrating stress-strain curves for the six exemplary embodiments of compressible non-fiber adjuncts of Example 11. DETAILED DESCRIPTION

[0137] Certain exemplary embodiments will now be described in order to provide a thorough understanding of the principles of the adjuncts, systems, and methods disclosed herein. One or more examples of these embodiments are illustrated in the accompanying drawings. Those of ordinary skill in the art will understand that the adjuncts, systems, and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments and that the scope of the application is defined solely by the claims. Features shown or described with respect to one exemplary embodiment can be combined with features of other embodiments. Such modifications and variations are intended to fall within the scope of the application.

[0138] ​​Surgical stapling assemblies are provided, as well as methods of manufacturing and using the same. Generally, the surgical stapling assemblies can include a staple cartridge having a compressible bioabsorbable non-fibrous adjunct configured to be releasably retained on the staple cartridge and a staple disposed therein. In some embodiments, the non-fibrous adjunct can be formed from a matrix including at least one melt bioabsorbable polymer and thus the non-fibrous adjunct can be three-dimensionally printed. In other embodiments, the non-fibrous adjunct can be formed, in part or in whole, by any suitable non-additive manufacturing process, such as injection molding, foaming, and molding processes, as understood by one skilled in the art. As discussed herein, a variety of adjuncts can be configured to compensate for variations in tissue properties, such as variations in tissue thickness, and / or to promote tissue ingrowth when the adjunct is stapled to tissue. For example, the adjunct can be configured such that the adjunct experiences a strain in a range of about 0.1 (10% deformation) to 0.9 (90% deformation) when under an applied stress in a range of about 30 kPa to 90 kPa. That is, the adjuncts described herein can be configured to deform from about 10% to 90% when under a stress of between (and / or including) about 30 kPa to 90 kPa, for example, when the adjunct is in a tissue deployed state.

[0139] Exemplary stapling assemblies can include various features to facilitate application of surgical staples, as described herein and shown in the drawings. However, those skilled in the art will appreciate that the stapling assemblies can include only some of these features and / or they can include a number of other features known in the art. The stapling assemblies described herein are merely intended to represent certain exemplary embodiments. Moreover, while the adjuncts are described in connection with surgical staple cartridge assemblies, the adjuncts can be used in connection with staple reloaders that are not based on staple cartridges or any type of surgical instrument.

[0140] Figure 1 An exemplary surgical stapling and severing device 100 adapted for use with an implantable adjunct is shown. The illustrated surgical stapling and severing device 100 includes a staple applying assembly 106, or end effector, having an anvil 102 pivotally coupled to an elongate staple channel 104. Thus, the staple applying assembly 106 is movable between an open position, as shown, and a closed position, wherein the anvil 102 is positioned adjacent the elongate staple channel 104 to engage tissue therebetween. The staple applying assembly 106 can be attached at its proximal end to an elongate shaft 108 forming a tool portion 110. When the staple applying assembly 106 is closed, or at least substantially closed, (e.g., the anvil 102 is moved from the open position to the closed position) the elongate shaft 108 can be moved relative to the staple applying assembly 106 to apply staples to tissue clamped between the anvil 102 and the elongate staple channel 104. Figure 1 The staple applying assembly 106 can be attached at its proximal end to an elongate shaft 108 forming a tool portion 110. When the staple applying assembly 106 is closed, or at least substantially closed, (e.g., the anvil 102 is moved from the open position to the closed position) the elongate shaft 108 can be moved relative to the staple applying assembly 106 to apply staples to tissue clamped between the anvil 102 and the elongate staple channel 104. Figure 1In the open position, the tool portion 110 can present a cross-section that is small enough for the staple applying assembly 106 to be inserted through a trocar. While the device 100 is configured to staple and transect tissue, surgical devices configured to staple but not transect tissue are also contemplated herein.

[0141] In various instances, the staple applying assembly 106 can be manipulated by a handle 112 connected to the elongate shaft 108. The handle 112 can include a user control such as a knob 114 that rotates the elongate shaft 108 and the staple applying assembly 106 about a longitudinal axis of the elongate shaft 108, and a closure trigger 116 that can be pivoted relative to a pistol grip 118 to close the staple applying assembly 106. For example, when the closure trigger 116 is clamped, a closure release button 120 can be present outwardly on the handle 112 such that the closure release button 120 can be depressed to unclamp the closure trigger 116 and open the staple applying assembly 106.

[0142] A firing trigger 122 that can be pivoted relative to the closure trigger 116 can cause the staple applying assembly 106 to both transect and staple tissue clamped therein. In various instances, multiple firing strokes can be employed using the firing trigger 122 to reduce the amount of force that needs to be applied by the surgeon’s hand per stroke. In certain embodiments, the handle 112 can include one or more rotatable indicator wheels, such as a rotatable indicator wheel 124 that can indicate the firing progress. If needed, a manual firing release lever 126 can allow the firing system to be retracted before the full firing progress is complete, and furthermore, in the event that the firing system jams and / or fails, the firing release lever 126 can allow the surgeon or other clinician to retract the firing system.

[0143] Additional details regarding the surgical stapling and transecting device 100 and other surgical stapling and transecting devices suitable for use with the present disclosure are described, for example, in U.S. Patent No. 9,332,984 and U.S. Patent Publication No. 2009 / 0090763, the disclosures of which are incorporated by reference herein in their entireties. Additionally, rather than including a handle, the surgical stapling and transecting device can have a housing configured to be coupled to a surgical robot, for example, as described in U.S. Patent Application No. 2019 / 0059889, the disclosure of which is incorporated by reference herein in its entirety.

[0144] As Figure 1 As further shown, the staple cartridge 200 can be used with the instrument 100. In use, the staple cartridge 200 is placed within and coupled to the elongate staple channel 104. While the staple cartridge 200 can have various configurations, in this illustrated embodiment, the staple cartridge 200 includes a deck 202 that supports a plurality of staple cavities 204. The staple cavities 204 are configured to receive staples 206 that are ejected therefrom by a staple firing assembly 208. The staple firing assembly 208 can include a sled 210 that is configured to be advanced through the staple cavities 204 to eject the staples 206 therefrom. The staple firing assembly 208 can also include a knife 212 that is configured to be advanced through the deck 202 to transect tissue clamped therein. In various instances, the staple firing assembly 208 can be configured to be advanced through the staple cavities 204 and the deck 202 in a single firing stroke. Figures 2A-2BThe staple cartridge 200 is shown in greater detail having a proximal end 202a and a distal end 202b with a longitudinal axis (L C ) extending therebetween. Thus, when the staple cartridge 200 is inserted into the elongate staple channel 104 Figure 1 ), the longitudinal axis (L C ) is aligned with the longitudinal axis (L S ) of the elongate shaft 108. Additionally, the staple cartridge 200 includes a longitudinal slot 210 defined by two opposing walls 210a, 210b and configured to receive at least a portion of a firing member of a firing assembly, such as the firing assembly 400 in Figure 4 , as discussed further below. As shown, the longitudinal slot 202 extends from the proximal end 202a toward the distal end 202b of the staple cartridge 200. It is also contemplated herein that the longitudinal slot 202 can be omitted in other embodiments.

[0145] The illustrated staple cartridge 200 includes staple cavities 212, 214 defined therein, wherein each staple cavity 212, 214 is configured to removably receive at least a portion of a staple (not shown). The number, shape, and location of the staple cavities can vary and can depend at least on the size and shape of the staples that are removably disposed therein. In this illustrated embodiment, the staple cavities are arranged in two groups of three longitudinally arranged rows, wherein a first group of staple cavities 212 is positioned on a first side of the longitudinal slot 210 and a second group of staple cavities 214 is positioned on a second side of the longitudinal slot 210. On each side of the longitudinal slot 210, and thus for each group of rows, the staple cavities of a first longitudinal row 212a, 214a extend along the longitudinal slot 210, a second row of staple cavities 212b, 214b extends along the first row of staple cavities 212a, 214a, and a third row of staple cavities 212c, 214c extends along the second row of staple cavities 212b, 214b. For each group of rows, the first row of staple cavities 212a, 214b, the second row of staple cavities 212b, 214b, and the third row of staple cavities 214c, 214c are parallel to each other and the longitudinal slot 210. Additionally, as shown, for each group of rows, the second row of staple cavities 212b, 214b is staggered relative to the first row of staple cavities 212a, 212c and the third row of staple cavities 214a, 214c. In other embodiments, the rows of staple cavities 212, 214 in each group are not parallel to each other and / or the longitudinal slot 210.

[0146] The staples that are releasably stored in the staple cavities 212, 214 can have various configurations. An exemplary staple 300 that can be releasably stored in each of the staple cavities 212, 214 is shown in its unfired (pre-deployed, unformed) configuration in Figure 3The illustrated staple 300 includes a crown (base) 302 and two legs 304 extending from each end of the crown 302. In this embodiment, the crown 302 extends in a linear direction and the staple legs 304 have the same unformed height, while in other embodiments, the crown can be a stepped crown, similar to the crown 2804c, 2806c, 2808c in Figure 28A , and / or the staple legs can have different unformed heights (see Figure 29 ). Additionally, prior to deployment of the staple 300, the staple crown 302 can be supported by a staple driver positioned within the staple cartridge 200, and concurrently, the staple legs 304 can be at least partially housed within the staple cavities 212, 214. Additionally, when the staple 300 is in its unfired position, the staple legs 304 can extend beyond the top surface of the staple cartridge 200, such as the top surface 206. In certain instances, as shown in Figure 3 , the tips 306 of the staple legs 304 can be sharp and pointed, which can cut into and penetrate tissue.

[0147] In use, the staples 300 can be deformed from the unfired position to the fired position such that the staple legs 304 move through the staple cavities 212, 214, penetrate tissue positioned between the anvil 102 and the staple cartridge 200, and contact the anvil 102. As the staple legs 304 are deformed against the anvil 102, the legs 304 of each staple 300 can capture a portion of the tissue within each staple 300 and apply a compressive force to the tissue. Additionally, the legs 304 of each staple 300 can be deformed downwardly toward the crown 302 of the staple 300 to form a staple trap region in which tissue can be captured. In various instances, the staple trap region can be defined between the inner surfaces of the deformed legs and the inner surface of the crown of the staple. For example, the size of the staple trap region can depend on several factors, such as the length of the legs, the diameter of the legs, the width of the crown, and / or the degree of leg deformation.

[0148] In some embodiments, all of the staples disposed within the staple cartridge 200 can have the same un-fired (pre-deployed, unformed) configuration. In other embodiments, the staples can include at least two groups of staples having different un-fired (pre-deployed, unformed) configurations relative to one another, e.g., varying in height and / or shape relative to one another, etc. For example, the staple cartridge 200 can include a first group of staples disposed within the first rows of staple cavities 212a, 214a having a first height, a second group of staples disposed within the second rows of staple cavities 212b, 214b having a second height, and a third group of staples disposed within the third rows of staple cavities 212c, 214c having a third height. In some embodiments, the first height, the second height, and the third height can be different, wherein the third height is greater than the first height and the second height. In other embodiments, the first height and the second height are the same, but the third height is different and greater than the first height and the second height. Other combinations of staples will be understood by one skilled in the art.

[0149] Additionally, the staples can include one or more outer coatings, e.g., a sodium stearate lubricant and / or an antimicrobial agent. The antimicrobial agent can be applied to the staples as its own coating or incorporated into another coating, such as a lubricant. Non-limiting examples of suitable antimicrobial agents include 5-chloro-2-(2,4-dichlorophenoxy)phenol, chlorhexidine, silver formulations (e.g., nanocrystalline silver), lauric arginate ethyl ester (LAE), octenidine, polyhexamethylene biguanide (PHMB), taurolidine, lactic acid, citric acid, acetic acid, and salts thereof.

[0150] Referring back to FIG. 1, Figures 2A-2B The staple cartridge 200 extends from a top or deck surface 206, which is configured as a tissue-facing surface, to a bottom surface 208, which is configured as a channel-facing surface. Thus, when the staple cartridge 200 is inserted into the elongate channel 104, as shown in FIG. 1, the top surface 206 faces the anvil 102 and the bottom surface 208 (obscured) faces the elongate channel 104. Figure 1

[0151] In some embodiments, the top surface 206 can include a surface feature defined therein. For example, the surface feature can be a recessed channel defined within the top surface 206. As shown in FIG. 2, the recessed channel can be configured to receive a portion of the anvil 102 when the anvil 102 and the staple cartridge 200 are coupled together. Figure 2C ​As shown in greater detail, a first recessed channel 216 surrounds each first staple cavity 212a, 214a. Each first recessed channel 216 is defined by a substantially triangular wall 216a having a proximally directed vertex, a distally directed vertex, and a laterally outwardly directed vertex. Additionally, each first recessed channel 216 includes a first floor 206a at a first height from the top surface 206. A second recessed channel 218 surrounds each second staple cavity 212b, 214b. Each second recessed channel 218 is defined by a substantially diamond-shaped wall 218a including a proximally directed vertex, a distally directed vertex, a laterally inwardly directed vertex, and a laterally outwardly directed vertex relative to the longitudinal axis. Additionally, each second recessed channel 218 includes a second floor 206b at a second height from the top surface 206. A third recessed channel 220 surrounds each third staple cavity 212c, 214c. Each third recessed channel 220 is defined by a substantially triangular wall 220a including a proximally directed vertex, a distally directed vertex, and a laterally inwardly directed vertex relative to the longitudinal axis. Additionally, each third recessed channel 220 includes a third floor 206c at a third height from the top surface 206. In some embodiments, the first height of the first recessed channel 216, the second height of the second recessed channel 218, and the third height of the third recessed channel 220 can have the same height. In other instances, the first height, the second height, and / or the third height can be different. Additional details regarding surface features and other exemplary surface features can be found in U.S. Patent No. 2016 / 0106427, which is incorporated herein by reference in its entirety. Additionally, as will be discussed in greater detail below, these recessed channels 216, 218, 220 can be used to interact with an adjunct, such as the adjunct 2600 in Figures 26A-26C , which can be releasably retained on the top surface of the cartridge prior to staple deployment.

[0152] Referring to Figure 4 and Figure 5 , a firing assembly, such as firing assembly 400, can be used with a surgical stapling and severing device, such as device 100 in Figure 1 . Firing assembly 400 can be configured to advance a wedge sled 500 having a wedge 502 configured to deploy staples from a staple cartridge 200 to a anvil, such as anvil 102 in Figure 1 , and a staple cartridge, such as staple cartridge 200 in Figure 1the tissue between the staple cartridge 200 in the tissue. Additionally, the E-beam 402 at the distal portion of the firing assembly 400 can fire the staples from the staple cartridge. During firing, the E-beam 402 can also pivot the anvil toward the staple cartridge and thus move the stapling assembly from the open position to the closed position. The illustrated E-beam 402 includes a pair of top pins 404, a pair of middle pins 406 that can follow a portion 504 of the wedge sled 500, and a bottom pin or foot 408. The E-beam 402 can also include a sharp cutting edge 410 that is configured to cut the captured tissue as the firing assembly 400 is advanced distally and thus toward the distal end of the staple cartridge. Additionally, an integrally formed proximally projecting top guide 412 and middle guide 414 that cradle each vertical end of the cutting edge 410 can further define a tissue-stapling region 416 to help direct tissue to the sharp cutting edge 410 before the tissue is cut. The middle guide 414 can also be used to engage and fire the staples within the staple cartridge by abutting the stepped central member 506 of the wedge sled 500, which affects staple formation by the stapling assembly 106.

[0153] In use, by pressing the closure trigger in the handle 100 to advance the E-beam 402 in the firing assembly 400, Figure 1 the anvil 102 in the staple cartridge 200 can be moved into the closed position. The anvil can position tissue against at least the top surface 206 of the staple cartridge 200 as in 2A through Figure 4 Figure 1 Once the anvil has been properly positioned, the staples 300 disposed within the staple cartridge in the handle 100 can be deployed. Figure 2C Figure 3 To deploy the staples from the staple cartridge, the sled 500 in the handle 100 can be moved from the proximal end toward the distal end of the cartridge body and thus toward the distal end of the staple cartridge as discussed above. When the firing assembly 400 in the handle 100 is advanced, the sled can contact and lift the staple drivers within the staple cartridge upward within the staple cavities 212, 214. In at least one example, the sled and the staple drivers can each include one or more ramps or inclined surfaces that can cooperate to move the staple drivers upward from their unfired positions. As the staple drivers are lifted upward within their respective staple cavities, the staples are advanced upward such that the staples emerge from their staple cavities and penetrate into the tissue. In various instances, the sled can move several staples upward simultaneously as part of the firing sequence.

[0154] To deploy the staples from the staple cartridge, the sled 500 in the handle 100 can be moved from the proximal end toward the distal end of the cartridge body and thus toward the distal end of the staple cartridge as discussed above. When the firing assembly 400 in the handle 100 is advanced, the sled can contact and lift the staple drivers within the staple cartridge upward within the staple cavities 212, 214. In at least one example, the sled and the staple drivers can each include one or more ramps or inclined surfaces that can cooperate to move the staple drivers upward from their unfired positions. As the staple drivers are lifted upward within their respective staple cavities, the staples are advanced upward such that the staples emerge from their staple cavities and penetrate into the tissue. In various instances, the sled can move several staples upward simultaneously as part of the firing sequence. Figure 5 Figure 4 To deploy the staples from the staple cartridge, the sled 500 in the handle 100 can be moved from the proximal end toward the distal end of the cartridge body and thus toward the distal end of the staple cartridge as discussed above. When the firing assembly 400 in the handle 100 is advanced, the sled can contact and lift the staple drivers within the staple cartridge upward within the staple cavities 212, 214. In at least one example, the sled and the staple drivers can each include one or more ramps or inclined surfaces that can cooperate to move the staple drivers upward from their unfired positions. As the staple drivers are lifted upward within their respective staple cavities, the staples are advanced upward such that the staples emerge from their staple cavities and penetrate into the tissue. In various instances, the sled can move several staples upward simultaneously as part of the firing sequence.

[0155] ​​​As discussed above, the stapling device can be used in combination with a compressible adjunct. Those skilled in the art will appreciate that while adjuncts are illustrated and described below, the adjuncts disclosed herein can be used with other surgical instruments and need not be coupled to a staple cartridge as described. Further, those skilled in the art will also appreciate that the staple cartridge need not be replaceable.

[0156] As discussed above, for some surgical staplers, the surgeon often needs to select an appropriate staple having an appropriate staple height for the tissue to be stapled. For example, the surgeon will utilize long staples for thick tissue and short staples for thin tissue. However, in some instances, the tissue being stapled does not have a uniform thickness and, therefore, the staple cannot achieve the desired firing configuration for each portion of the tissue being stapled (e.g., thick and thin portions of tissue). The non-uniform thickness of the tissue can also result in undesirable leakage and / or tearing of the tissue at the staple site when using staples having the same or substantially greater height, particularly when the staple site is exposed to intra-tissue pressure at the staple site and / or along the staple line.

[0157] Accordingly, various embodiments of non-fibrous adjuncts are provided that can be configured to compensate for variations in the thickness of tissue captured within a fired (deployed) staple to avoid the need to consider staple height when stapling tissue during a surgical procedure. That is, the adjuncts described herein can allow a set of staples having the same or similar height to be used to staple tissue having varying thicknesses (e.g., from thin to thick tissue), while also combining with the adjunct to provide sufficient compression of the tissue within and between the fired staples. Accordingly, the adjuncts described herein can maintain proper compression of thin or thick tissue stapled to the adjunct, thereby minimizing leakage and / or tearing of the tissue at the staple site.

[0158] Alternatively or additionally, the non-fibrous adjuncts can be configured to promote tissue ingrowth. In various instances, it is desirable to promote tissue ingrowth into an implanted adjunct to promote healing of the treated tissue (e.g., stapled tissue and / or incised tissue) and / or to accelerate recovery of the patient. More particularly, tissue ingrowth into an implanted adjunct can reduce the incidence, extent, and / or duration of inflammation at the surgical site. Tissue ingrowth into and / or around an implanted adjunct can control the spread of infection, for example, at the surgical site. Vascularization, particularly white blood cells, ingrowth into and / or around an implanted adjunct can combat infection in and / or around the implanted adjunct and adjacent tissue. Tissue ingrowth can also promote acceptance of a foreign body (e.g., an implanted adjunct and staples) by the patient’s body and can reduce the likelihood that the patient’s body will reject the foreign body. Rejection of a foreign body can result in infection and / or inflammation at the surgical site.

[0159] Unlike conventional adjuncts (e.g., non-three-dimensionally printed adjuncts such as foam adjuncts and woven / nonwoven non-fiber adjuncts), these non-fiber adjuncts are three-dimensional (3D) printed and thus can be formed with consistent and reproducible microstructures (cells). That is, unlike other manufacturing methods, 3D printing significantly improves control over microstructure features such as placement and connection of elements. Thus, both the variability of the microstructure and the attendant properties of the adjuncts of the present disclosure are reduced as compared to conventional adjuncts. For example, the adjuncts of the present disclosure can be structured such that they compress a pre-determined amount in a substantially uniform manner. Fine control over the microstructure can also allow customization of the porosity of the adjunct to enhance tissue ingrowth. The non-fiber adjuncts of the present disclosure can also be adapted for use with a variety of staples and tissue types.

[0160] Generally, the adjuncts provided herein are designed and positioned at the top of a staple cartridge, such as staple cartridge 200. When the staples are fired (deployed) from the cartridge, the staples penetrate the adjunct and into tissue. As the legs of the staples deform against an anvil positioned opposite the staple cartridge, the deformed legs capture a portion of the adjunct and a portion of the tissue within each staple. That is, at least a portion of the adjunct becomes positioned between the tissue and the fired staple as the staple is fired into the tissue. While the adjuncts described herein can be configured to attach to a staple cartridge, it is also contemplated herein that the adjuncts can be configured to cooperate with other instrument components such as the anvil of a surgical stapler. Those of ordinary skill in the art will appreciate that the adjuncts provided herein can be used with replaceable cartridges or staple reloaders that are not based on a cartridge.

[0161] Method of suturing tissue

[0162] Figures 6A-6B An exemplary embodiment of a stapling assembly 600 is shown that includes a staple cartridge 602 and an adjunct 604. For simplicity, the adjunct 604 is generally shown and described in Figures 6A-6B various structural configurations are described in greater detail below. Aside from the differences described in detail below, the staple cartridge 602 can be similar to the staple cartridge 200 Figures 1-3 ), and thus common features are not described in detail herein. As shown, the adjunct 604 is positioned against the staple cartridge 602. While partially obscured in Figures 6A-6B the staple cartridge 602 includes staples 606 that can be similar to the staples 300 in Figure 3 the staple cartridge 602 includes staples 606 that can be similar to the staples 300 in

[0163] In the illustrated embodiments, the appendage 604 may mate with at least a portion of the top surface or platform surface 608 of the staple cartridge 602. In some embodiments, the top surface 608 of the staple cartridge 602 may include one or more surface features, three-dimensional, such as... Figure 2A and Figure 2C The recessed channels 216, 218, and 220 are shown. This one or more surface features may be configured to engage the appendage 604 to prevent undesirable movement of the appendage 604 relative to the staple cartridge 602 and / or to prevent premature release of the appendage 604 from the staple cartridge 602. Exemplary surface features are described in U.S. Patent Publication No. 2016 / 0106427, the entire contents of which are incorporated herein by reference.

[0164] Figure 6B It shows that it was placed with Figure 1 The surgical end effector 106 is similar to the surgical end effector 601, residing within the elongated staple channel 610 and connected to the suture assembly 600 of the elongated staple channel. The anvil 612 is pivotally connected to the elongated staple channel 610 and thus moves between an open and closed position relative to the elongated staple channel 610 (and therefore relative to the staple cartridge 602). Figure 6B The closed position is shown, and the tissue gap T is created between the staple cartridge 602 and the anvil 612. G More specifically, the interstitial space T G The distance between the tissue-compression surface 612a of the anvil 612 (e.g., the tissue engagement surface between the pin-forming recesses in the anvil) and the tissue contact surface 604a of the appendage 604 is defined. In this illustrated embodiment, both the tissue-compression surface 612a of the anvil 612 and the tissue contact surface 604a of the appendage 604 are planar or substantially planar (e.g., planar within manufacturing tolerances). Therefore, when the anvil 612 is in the closed position, as... Figure 6B As shown, when no tissue is placed in it, the tissue gap T G They are typically uniform (e.g., nominally identical within manufacturing tolerances). In other words, the interstitial space T G The trans-end actuator 601 (e.g., in the y-direction) is typically constant (e.g., constant within manufacturing tolerances). In other embodiments, the tissue-compression surface of the anvil may include a stepped surface having longitudinal steps between adjacent longitudinal portions, thus creating a stepped profile (e.g., in the y-direction). In such embodiments, the tissue gap T G It can change.

[0165] The adjunct 604 can be compressible to allow for different heights to which the adjunct can compress, thereby compensating for different tissue thicknesses captured within the deployed staples. The adjunct 604 has an uncompressed (un-deformed) or pre-deployment height, and is configured to deform to one of a plurality of compressed (deformed) or deployed heights. For example, the adjunct 604 can have an uncompressed height that is greater than a firing height of the staples 606 disposed within the cartridge 602 (e.g., a height (H) of the fired staples 606a in Figure 7 That is, the adjunct 604 can have an un-deformed state in which a maximum height of the adjunct 604 is greater than a maximum height of the fired staples (e.g., staples in a formed configuration). In one embodiment, the uncompressed height of the adjunct 604 can be about 10% greater, about 20% greater, about 30% greater, about 40% greater, about 50% greater, about 60% greater, about 70% greater, about 80% greater, about 90% greater, or about 100% greater than the firing height of the staples 606. In certain embodiments, the uncompressed height of the adjunct 604 can be more than 100% greater than the firing height of the staples 606, for example.

[0166] In use, once the surgical stapling and severing device (e.g., the device 100 in Figure 1 Once the tissue is positioned between the anvil 612 and the stapling assembly 600, the surgical stapler can be actuated, e.g., as discussed above, to clamp the tissue between the anvil 612 and the stapling assembly 600 (e.g., between the tissue-compression surface 612a of the anvil 612 and the tissue-contacting surface 604a of the adjunct 604) and deploy the staples from the cartridge through the adjunct and into the tissue to staple and attach the adjunct to the tissue.

[0167] As shown in Figure 7 When the staples 606 are fired, the tissue (T) and a portion of the adjunct 604 are captured by the fired staples 606a. As discussed above, the fired staples 606a each define a containment region therein for housing the captured adjunct 604 and tissue (T). The containment region defined by the fired staples 606a is at least partially limited by a height (H) of the fired staples 606a. For example, the height of the fired staples 606a can be about 0.160 inches or less. In some embodiments, the height of the fired staples 606a can be about 0.130 inches or less. In one embodiment, the height of the fired staples 606a can be about 0.020 inches to 0.130 inches. In another embodiment, the height of the fired staples 606a can be about 0.060 inches to 0.160 inches.

[0168] As noted above, the adjunct 604 can be compressed within a plurality of fired staples, regardless of whether the thickness of tissue captured within the staples is the same or different within each fired staple. In at least one example embodiment, the staples within a staple line or row of staples can be deformable such that the firing height is, for example, about 2.75 mm, where the tissue (T) and adjunct 604 can be compressed within this height. In certain instances, the tissue (T) can have a compression height of about 1.0 mm and the adjunct 604 can have a compression height of about 1.75 mm. In certain instances, the tissue (T) can have a compression height of about 1.50 mm and the adjunct 604 can have a compression height of about 1.25 mm. In certain instances, the tissue (T) can have a compression height of about 1.75 mm and the adjunct 604 can have a compression height of about 1.00 mm. In certain instances, the tissue (T) can have a compression height of about 2.00 mm and the adjunct 604 can have a compression height of about 0.75 mm. In certain instances, the tissue (T) can have a compression height of about 2.25 mm and the adjunct 604 can have a compression height of about 0.50 mm. Thus, the sum of the compression heights of the captured tissue (T) and adjunct 604 can equal or at least substantially equal the height (H) of the fired staples 606a.

[0169] Additionally, most structures generally behave in a manner in which the strain (deformation) of the material increases as the stress applied to the material increases. However, for surgical stapling, it is desirable for the strain of the adjunct to increase over a relatively narrow range of stresses, and thus, as discussed in greater detail below, the adjuncts described herein can be structured in such a manner that they can exhibit a flat or moderately sloped "stress plateau." Generally, a stress plateau is a regime in the stress-strain curve of a cellular material upon compression that corresponds to progressive cell collapse by elastic buckling and depends on the properties of the solid of the manufacturing material. That is, as a given structure deforms under compression, the strain can increase without a significant increase in stress, and thus, result in a stress plateau, advantageously delaying densification (e.g., solid height) of the structure. Thus, the adjuncts described herein can be designed to experience compression over an extended period of time over a range of stresses that are typically applied to the adjunct when it is in a tissue deployment state (e.g., when the adjunct is stapled to a tissue body).

[0170] Accordingly, the structure of the adjunct can be designed such that when the adjunct and tissue are captured within the firing staple, the adjunct can experience a strain in the range of 0.1 to 0.9 when under an applied stress in the range of 30 kPa to 90 kPa. The applied stress when the adjunct is in the tissue deployed state is the stress applied by the sutured tissue against the adjunct. Those skilled in the art will appreciate that the tissue applied stress depends on various suturing conditions (e.g., tissue thickness, formed staple height, intra-tissue pressure). For example, high blood pressure is generally considered to be 210 mmHg, and thus it is desirable for the adjuncts of the present disclosure to withstand an applied stress equal to or greater than 210 mmHg without densifying for a predetermined period of time. In other embodiments, the strain can be in the range of about 0.1 to 0.8, about 0.1 to 0.7, about 0.1 to 0.6, about 0.2 to 0.8, about 0.2 to 0.7, about 0.3 to 0.7, about 0.3 to 0.8, about 0.3 to 0.9, about 0.4 to 0.9, about 0.4 to 0.8, about 0.4 to 0.7, about 0.5 to 0.8, or about 0.5 to 0.9. Accordingly, the adjuncts described herein can be structured to be deformable and thus not reach their solid height under a predetermined amount of applied stress.

[0171] To design an adjunct structured to experience a strain in the range of about 0.1 to 0.9 when under an applied stress in the range of about 30 kPa to 90 kPa, the principles of Hooke’s Law (F = kD) can be used. For example, knowing the force (stress) that will be applied to the tissue deployed adjunct, the adjunct can be designed to have a predetermined stiffness (k). The stiffness can be set by tuning the geometry of the adjunct (e.g., the shape of the cells, the wall thickness, height, and / or interconnectivity, e.g., the angles and spaces between cells and / or the diameter of the struts of the cells and / or the interconnectivity of the struts of the cells, e.g., the angles and spaces between struts). Additionally, the adjunct can be designed to have a maximum compression displacement amount for a minimum tissue thickness (e.g., 1 mm), and thus the length of the displacement D can be the combination of the minimum tissue thickness (e.g., 1 mm) plus the thickness of the adjunct when sutured to tissue at a given maximum staple height (e.g., 2.75 mm). By way of example, in one embodiment, the adjunct can be structured to have a height greater than the maximum formed suture height of 2.75 mm, and can be compressed to a height of 1.75 mm when sutured to tissue having a minimum thickness of 1 mm. Accordingly, the adjunct can vary in compressibility to maintain a constant length of the displacement D, such that the captured tissue and the stiffness (k) and total thickness (D) of the adjunct can apply 3 gf / mm 2of stress. It should be noted that one skilled in the art will appreciate that the foregoing equations can be modified to account for changes in temperature, for example, when the adjunct is brought from room temperature to body temperature after implantation. Additionally, the foregoing discussion of Hooke's Law represents an approximation. Thus, one skilled in the art will appreciate that principles of large deformation mechanics (also known as finite elasticity) can be used to more accurately predict the relationship between stress and strain by using constitutive equations tailored to the material of interest.

[0172] Thus, the compressibility profile of the adjunct can be controlled by at least the structural configuration of the cells and their interconnectivity. Thus, the structural configuration of the cells can be tailored to achieve an adjunct having desired mechanical properties for suturing tissue. Because there is a finite range of intra-tissue pressure, tissue thickness, and formed staple height, an appropriate geometry of the adjunct, and thus the cells, can be determined that can effectively allow the adjunct to undergo a desired amount of strain at a substantially constant rate while applying a desired amount of stress. In other words, the structural configuration of the cells can be designed to produce an adjunct that can apply a substantially continuous desired stress (e.g., at least 3 gf / mm 2 ) to a sutured tissue for a given amount of time over a range of suturing conditions. That is, as described in greater detail below, the adjuncts of the present disclosure are formed of a compressible material and are geometrically configured to allow the adjunct to compress to different heights within a predetermined plane when sutured to a tissue. Furthermore, this changing response by the adjunct can also allow the adjunct to maintain its application of a continuous desired stress to a tissue when exposed to fluctuations in intra-tissue pressure, which can occur when the adjunct is sutured to a tissue (e.g., peaks in blood pressure).

[0173] Attachment

[0174] The adjuncts can have a variety of configurations. The adjuncts generally include a tissue-contacting surface and a cartridge-contacting surface with an elongate body (e.g., internal structure) positioned therebetween. In certain embodiments, the tissue-contacting surface and / or the cartridge-contacting surface can have a different structure than the elongate body, thereby forming a tissue-contacting layer and a cartridge-contacting layer. As described in greater detail below, the adjuncts can have a strut-based configuration, a non-strut-based configuration, or a combination thereof.

[0175] Additionally, each example adjunct is illustrated in a partial form (e.g., not full length), and thus one skilled in the art will appreciate that the length of the adjunct (i.e., along its longitudinal axis (L A)) can be longer, as identified in each embodiment. The length can vary based on the length of the cartridge or anvil. The width can also vary as desired. Additionally, each example adjunct is configured to be positioned on the surface of the cartridge or anvil such that the longitudinal axis L of each adjunct is aligned with the longitudinal axis of the cartridge or anvil (L A ) and extends along that longitudinal axis. The adjuncts are structured to compress when exposed to a compressive force (e.g., stress or load).

[0176] The adjuncts described herein can have various average lengths, widths, and thicknesses. For example, in some embodiments, the adjuncts can have an average length in a range of about 20 mm to 100 mm or about 40 mm to 100 mm. In other embodiments, the adjuncts can have an average width in a range of about 5 mm to 10 mm. In yet other embodiments, the adjuncts can have an average thickness in a range of about 1 mm to 6 mm, about 1 mm to 8 mm, about 2 mm to 6 mm, or about 2 mm to 8 mm. In one embodiment, an example adjunct can have an average length in a range of about 20 mm to 100 mm, an average width in a range of 5 mm to 10 mm, and an average thickness in a range of about 1 mm to 8 mm.

[0177] The elongated body can be formed from one or more lattice structures each formed from interconnected unit cells. While the unit cells can have various configurations, in some embodiments, the unit cells can be strutless-based unit cells, while in other embodiments, the unit cells can be strut-based unit cells. A strut can be a non-hollow rod or bar formed entirely or substantially from a solid material. In certain embodiments, the one or more lattice structures can be formed from interconnected repeating unit cells. Additionally, in certain embodiments, the elongated body can include at least one lattice structure formed from strutless-based unit cells and at least one lattice structure formed from strut-based unit cells (see Figure 54 ).

[0178] Each lattice structure extends from a first surface (e.g., a top surface) to a second surface (e.g., a bottom surface). Depending on the overall structural configuration of the adjunct, at least a portion of the first surface of at least one lattice structure can function as a tissue-contacting surface of the adjunct, and at least a portion of the second surface of at least one lattice structure can function as a cartridge-contacting surface of the adjunct. Those skilled in the art will appreciate that each lattice structure can have additional tissue-contacting surfaces (e.g., one or more lateral side surfaces relative to the top surface).

[0179] In certain embodiments, the adjunct can include a tissue-contacting layer disposed on at least a portion of the first surface of the at least one lattice structure of the internal structure. The tissue-contacting layer has a thickness extending between the first surface (e.g., a top surface) and the second surface (e.g., a bottom surface). Thus, the first surface of the tissue-contacting layer, alone or in combination with at least a portion of the first surface of the at least one lattice structure, can serve as a tissue-contacting surface of the resulting adjunct. The tissue-contacting layer can have a variety of configurations. For example, in some embodiments, the tissue-contacting layer is in the form of a lattice structure formed of interconnected repeating cells, which can be different from the lattice structure of the elongated body, while in other embodiments, the tissue-contacting layer is in the form of a film.

[0180] Alternatively or in addition, the adjunct can include a pocket-contacting layer disposed on at least a portion of the second surface of the at least one lattice structure. The pocket-contacting layer can have a thickness extending from the first surface (e.g., a top surface) to the second surface (e.g., a bottom surface). Thus, the second surface of the pocket-contacting layer, alone or in combination with at least a portion of the second surface of the at least one lattice structure, can serve as a pocket-contacting surface of the resulting adjunct. The pocket-contacting layer can have a variety of configurations. For example, in some embodiments, the pocket-contacting layer is in the form of a lattice structure formed of interconnected repeating cells, which can be different from the lattice structure of the elongated body, while in other embodiments, the pocket-contacting layer is in the form of a film. In some embodiments, the film can be a pressure sensitive adhesive, while in other embodiments, the film can include one or more attachment features extending therefrom.

[0181] Non-stent based attachment

[0182] As noted above, the adjunct can include a lattice structure formed of strutless-based unit cells (e.g., repeating strutless-based unit cells). In other words, in contrast to strut-based unit cells, which are characterized by the presence of acute or sharp angles, strutless-based unit cells can be characterized by curved surfaces. For example, the unit cells can be based on triply periodic minimal surfaces (TPMS). A TPMS is a minimal surface that repeats itself in three dimensions. As used in this specification, the term “minimal surface” refers to a minimal surface as known in mathematics. Thus, in some embodiments, the unit cells can be Schwarz structures (e.g., Schwarz-P, Schwarz Diamond), modified Schwarz structures, helicoid (e.g., Schoen Gyroid) structures, cosine structures, and coke can structures.

[0183] As discussed in greater detail below, strutless cells can have various structural configurations (e.g., height, width, wall thickness, shape). In some embodiments, the strut-based cells of the adjunct can be substantially uniform (e.g., nominally the same within manufacturing tolerances), while in other embodiments at least a portion of the strutless cells of the adjunct can vary in shape and / or size relative to the remainder of the strut-based cells.

[0184] For example, in some embodiments, each of the strutless cells can have a wall thickness of about 0.05 mm to 0.6 mm. In certain embodiments, the wall thickness can be about 0.1 mm to 0.3 mm. In one embodiment, the wall thickness can be about 0.2 mm. In certain embodiments, the wall thickness of all of the strutless cells of the adjunct can be substantially uniform (e.g., nominally the same within manufacturing tolerances). In other embodiments, for example, where the adjunct is formed of two or more groups of cells, each group of cells can have a different wall thickness. For example, in one embodiment, the adjunct can include first repeating cells each having a first wall thickness, second repeating cells each having a second wall thickness greater than the first wall thickness, and third repeating cells each having a third wall thickness greater than the second wall thickness. Alternatively or additionally, the first repeating cells can have a first height (e.g., maximum height), a second height (e.g., maximum height) greater than the first height, and a third height (e.g., maximum height) greater than the second height.

[0185] In some embodiments, the surface to volume ratio of each cell can be about 5 to 30. In certain embodiments, the surface to volume ratio of each cell can be about 7 to 20.

[0186] Schwarz-P structure

[0187] Figures 8A-8F is an exemplary embodiment of an adjunct 800 having a tissue-contacting surface 802 and a cartridge-contacting surface 804. The adjunct 800 includes interconnected repeating strutless cells 810, one of which is shown in Figures 9A-9BFurther details are shown in greater detail. While adjunct 800 is shown as having four longitudinal rows (LI, L2, L3, L4) each having 20 repeating cells 810, those of skill in the art will appreciate that the number of rows and the number of cells of an adjunct can depend at least on the size and shape of the cartridge and / or anvil to which the adjunct is to be applied, and thus the adjunct is not limited to the number of longitudinal rows and cells shown in the figures. Additionally, while only one type of repeating strutless cell is shown, in other embodiments, the adjunct can be formed from a combination of a first repeating strutless cell and a second repeating strutless cell that is different from the first repeating strutless cell, etc.

[0188] In view of the fact that adjunct 800 is formed from repeating cells 810 having substantially the same structural configuration (e.g., nominally the same within manufacturing tolerances), the following discussion is with respect to one repeating cell 810. As shown, repeating cell 810 has a top portion 812, a bottom structure 814, and an intermediate portion 816 extending therebetween. Figures 9A-9B

[0189] In the illustrated embodiment, repeating cell 810 is configured as a Schwarz-P structure, and thus, the surface profile of cell 810 is defined by a minimal surface. That is, the exterior surface 820 and the interior surface 822 of cell 810 are each defined by a minimal surface. Thus, in the illustrated embodiment, exterior surface 820 and interior surface 822 are generally concave, thereby forming arcuate sides 821 of cell 810. Additionally, interior surface 822 defines an interior volume 824 of cell 810. Thus, cell 810 can be characterized as being hollow. The Schwarz-P minimal surface can be functionally represented as: cos(x) + cos(y) + cos(z) = 0.

[0190] Cell 810 also includes a connection interface 826, which can be used to interconnect cell 810 to other cells 810, thereby forming adjunct 800. As shown, connection interface 826 includes a first connection portion 828 and a second connection portion 830. In the illustrated embodiment, first connection portion 828 is a tab that extends from the top portion 812 of cell 810, and second connection portion 830 is a tab that extends from the bottom structure 814 of cell 810. In other embodiments, however, the connection interface 826 can be configured in other ways, such as by having the first and second connection portions 828, 830 extend from the intermediate portion 816 of cell 810, etc. Figures 8A-8E ​The adjunct 800 shown in FIG. 8B. In the illustrated embodiment, the cell includes six connection interfaces 826 that form six outermost surfaces of the cell 810, e.g., top and bottom outermost surfaces 827a, 827b, left and right outermost surfaces 829a, 829b, and front and back outermost surfaces 831a, 831b. The top and bottom outermost surfaces 827a, 827b are generally planar (e.g., planar within manufacturing tolerances) relative to each other and offset in the x-direction, the left and right outermost surfaces 829a, 829b are generally planar (e.g., planar within manufacturing tolerances) relative to each other and offset in the y-direction, and the front and back outermost surfaces 831a, 831b are generally planar (e.g., planar within manufacturing tolerances) relative to each other and offset in the z-direction. Thus, the total outer surface of the cell 810 includes planar surfaces (e.g., the outermost surfaces 827a, 827b, 829a, 829b, 831a, 831b) and non-planar surfaces (e.g., the outer surface 820 extending between the connection interfaces 826). Additionally, because the adjunct 800 is formed only of repeating cells 810, the top portion 812 including the top outermost surface 812a forms the tissue-contacting surface 802 of the adjunct 800, and the bottom structure 814 of the cell forms the reservoir-contacting surface 804 of the adjunct 800 (e.g., in the x-direction). Thus, the tissue-contacting surface 802 is formed of planar and non-planar surfaces.

[0191] Additionally, based on the overall geometry of the repeating cells 810 and their interconnection at the corresponding connection interfaces 826 where they correspond to one another, the overall outer surface of the resulting adjunct 800 is formed by substantially planar (e.g., planar within manufacturing tolerances) surfaces separated by non-planar surfaces. As shown, the top and bottom outermost surfaces 850a, 850b of the adjunct 800 are farthest from a bisector extending in the YZ plane, the left and right outermost surfaces 852a, 852b of the adjunct 800 are farthest from a bisector extending in the XZ plane, and the front and back outermost surfaces 854a, 854b of the adjunct are farthest from a bisector extending in the XY plane. Additionally, as shown, the top and bottom outermost surfaces 850a, 850b are substantially planar (e.g., planar within manufacturing tolerances) relative to one another and offset in the x-direction, the left and right outermost surfaces 852a, 852b are substantially planar (e.g., planar within manufacturing tolerances) relative to one another and offset in the y-direction, and the front and back outermost surfaces 854a, 854b are substantially planar (e.g., planar within manufacturing tolerances) relative to one another and offset in the z-direction. Thus, these outermost surfaces 850a, 850b, 852a, 852b, 854a, 854b form planar segments of the outer surface of the adjunct 800. It can be appreciated that the portions of the adjunct 800 extending between these outermost surfaces 850a, 850b, 852a, 852b, 854a, 854b are defined by the outer surfaces 820 of adjacent cells 810, thereby forming non-planar surfaces of the outer surface of the adjunct 800.

[0192] As further shown, the six connection interfaces 826 define respective circular openings in fluid communication with the interior volume 824 of the cell 810. Thus, the cell 810 has openings in all six Cartesian sides (indicated as arrows 1, 2, 3, 4, 5, 6 in FIG. 8B). Figure 9B These openings can provide a variety of functions, such as: facilitating connection with adjacent cells; creating openings that can allow for tissue growth immediately upon suturing of the adjunct to tissue; allowing for drainage of manufacturing materials used in production of the resulting adjunct, such as materials used during a 3D manufacturing process; allowing for easy transfer of bodily fluids throughout the adjunct; contributing to mechanical properties of the adjunct, such as creating a compression profile that blocks densification of the adjunct; and / or minimizing the solid height of the fully compressed adjunct.

[0193] Further, when the cells 810 are interconnected to one another at the corresponding connection interfaces (e.g., at least two connection interfaces), hollow tubular interconnects 828 (e.g., lumens) are formed therebetween, as shown in FIG. 8B. Figures 8D-8EAs shown, the interconnects allow the interior volumes 824 of the interconnected cells 810 to be in fluid communication with one another. Thus, a continuous network of channels or pathways exists within the adjunct. Accordingly, when the adjunct 800 is sutured to tissue (T) and is in a tissue deployed state, as Figure 8G shown, one or more fluids (including cells entering the adjunct 800), for example, can migrate through the adjunct 800 in the tissue deployed state through the interconnected cells, for example, through the openings of the connection interfaces 826a of the top portions 812 of at least one cell 810, as Figure 8G shown, and thus can ultimately accelerate tissue ingrowth within the adjunct 800. That is, while the adjunct 800 is in the tissue deployed state, at least a portion of the hollow tubular interconnects 828 can at least partially maintain fluid communication between at least a portion or through all of the interior volumes of the cells 810, and thus encourage cell mobility throughout the adjunct 800.

[0194] While the hollow tubular interconnects 828 define openings that can have various dimensions (e.g., diameters), in some embodiments, the diameter of the openings can be about 100 microns to 3500 microns. For example, the diameter of the openings can be about 100 microns to 2500 microns or about 500 microns to 2500 microns. In certain embodiments, the diameter of the openings can be about 945 microns to 1385 microns. In one embodiment, the diameter of the openings can be greater than 2000 microns. In certain embodiments, the diameter of all of the openings is substantially the same (e.g., nominally the same within manufacturing tolerances). As used herein, the “diameter” of an opening is the greatest distance between any pair of vertices of the opening.

[0195] As a result of the repeating cells 810 being interconnected to one another at corresponding connection interfaces 826, the adjunct 800 is in the form of a lattice structure having predetermined compression regions 830 and predetermined non-compression regions 840, as Figure 8C more clearly shown. While the predetermined compression regions 830 and the predetermined non-compression regions 840 can have various configurations, in this illustrated embodiment, the predetermined compression regions 830 are defined by the cells 810 and the predetermined non-compression regions 840 are in the form of voids 845 defined between the cells 810. In this embodiment, each void 845 is formed between four adjacent interconnected cells 810. For example, as Figure 8F shown, a void 845a is defined between four adjacent cells 810a, 810b, 810c, 810d. Thus, the space existing between adjacent cells defines a predetermined non-compression region. In other words, the non-compression regions 840 of the adjunct are not defined by the interior volumes of the cells.

[0196] As described in more detail below, the structural configuration of repeating cells allows the cells to move along their height H (see below) for a period of time under applied stress. Figure 9A The cells deform or buckle continuously at different locations (e.g., until opposite sides of the inner surfaces of the cells contact each other). Therefore, during such a period, the cells can deform or buckle at a constant or substantially constant rate under applied stress (e.g., 30 kPa to 90 kPa). In other words, in some embodiments, the repeated cell structure can result in stress plateaus, for example, as... Figure 11 It is shown schematically in the middle.

[0197] Figures 10A-10D The illustration shows a repeating cell (e.g., Figures 8A-9B Cell 810 in the diagram describes the compressive behavior under a certain range of applied stress. Specifically, in... Figure 10A The repeated cell 1010 is shown in a pre-compressed (undistorted) state; Figure 10B The repeating cell is shown in a first compressed state, where each of the top portion 1012 and the bottom portion 1014 of cell 1010 begins to compress towards the middle portion 1016 of cell 1010, causing the middle portion 1016 to begin to deflect; Figure 10C The repeating cell is shown in a second compressed state, where the middle portion 1016 continues to deflect outwards; and... Figure 10D The repeating cell is shown in a dense state, wherein the opposite sides 1018a, 1018b of the inner surface 1018 of the middle portion 1016 are in contact with each other, such that the cell 810 reaches its solid height.

[0198] exist FIG. 11 The diagram schematically illustrates the undeformed state U of repeating cell 1010. FIG. 10A ), compression states C1, C2 ( FIGS. 10B-10C ) and dense state D( FIG. 10D The relationship between the stress-strain curve of the obtained appendage and the stress-strain curve.

[0199] The stress-strain response of the adjunct begins with an elastic deformation (bending) characterized by a Young's modulus, e.g., as the repeating units begin to deform from their uncompressed state toward their first compressed state. This elastic deformation continues until a yield stress is reached. Once the yield stress is reached, a stress plateau can occur, which corresponds to progressive cell collapse by elastic buckling, e.g., as the repeating cells continue to deform through their first compressed state and second compressed state. Those skilled in the art will appreciate that the stress plateau depends at least on the properties of the material from which the cells are manufactured. The stress plateau continues until densification occurs, which indicates that the cells are collapsing throughout the adjunct, e.g., as the repeating cells reach their densified state, and thus, the adjunct has reached its solid height.

[0200] Those skilled in the art will appreciate that the stress-strain curve of the adjunct depends on various factors, e.g., uncompressed height, constituent ingredients (including material properties), and / or structural configuration. By way of example, Table 1 below shows the stress-strain response of an exemplary adjunct, which differs only in uncompressed height (UH), and which is compressed to have a first compressed height (CH1) of 1.75 mm at an applied stress of 30 kPa, a second compressed height (CH2) of 0.75 mm at an applied stress of 90 kPa, and a third compressed height (CH3) of 0.45 mm at an applied stress of 90 kPa.

[0201] Table 1: Stress-strain relationships for various adjunct heights

[0202]

[0203] In another embodiment, the repeating-based strutless cells can be a modified Schwarz-P structure. For example, the Schwarz-P structure can be stretched in one or more directions to form a stretched Schwarz-P structure, e.g., as shown in FIG. 12A Alternatively or additionally, in certain embodiments, the wall thickness of the Schwarz-P structure can be thinned. For example, as shown in FIG. 12B the Schwarz-P structure is stretched and thinned. In yet another embodiment, as shown in FIG. 12C the Schwarz-P structure can be trimmed, e.g., where the height of the top portion H T (see FIG. 9A ) and / or the bottom portion H B (see FIG. 9A ) of the Schwarz-P structure is reduced. Alternatively or in addition to the foregoing exemplary modifications, additional openings can be added through the walls of the Schwarz-P structure, e.g., as shown in FIG. 12D which can help to densify the resulting adjunct.

[0204] The repeat-based strutless unit cell can take the form of other TPMS structures. For example, as shown in FIG. 13A The repeat-based strutless unit cell 1300 can be formed from a sheet of diamond structure with a diamond minimal surface having a Schwarz D lattice structure, as shown in

[0205] sin(x)sin(y)sin(z) + sin(x)cos(y)cos(z) + cos(x)sin(y)cos(z) + cos(x)cos(y)sin(z) = 0. FIG. 13B An exemplary adjunct 1310 formed from the repeat unit cell 1300 and thus the sheet of diamond structure is shown in

[0206] In another embodiment, as shown in FIG. 14A The repeat-based strutless unit cell 1400 can be a helicoid structure. The helicoid minimal surface can be functionally expressed as:

[0207] sin(x)cos(y) + sin(y)cos(z) + sin(z)cos(x) = 0.

[0208] FIG. 14B An exemplary adjunct 1410 formed from the repeat unit cell 1500 and thus the helicoid structure is shown in FIG. 15A In other embodiments, the repeat-based strutless unit cell can be in the form of a cosine structure 1500 FIG. 16A ) or in the form of a coke can structure 1600 FIG. 15B and FIG. 16B An exemplary adjunct 1510, 1610 formed from the respective repeat unit cell 1500 (cosine structure), 1600 (coke can structure) is shown.

[0209] Edge conditions

[0210] In some embodiments, certain strutless unit cells when interconnected to form an adjunct can create undesirable edge conditions for tissue stapling. For example, when tissue slides across an adjunct during use, the edge conditions can cause at least a portion of the adjunct to interact with the tissue in a manner that prematurely detaches the adjunct from the cartridge. These edge conditions can be a result of the geometry (e.g., having substantially planar (e.g., planar within manufacturing tolerances) and non-planar outer surfaces) and the interconnectivity of the strutless unit cells that make up the adjunct. Thus, to improve these edge conditions, and thus inhibit premature detachment of the adjunct, an outer layer having a different geometry can be placed on top of one or more tissue-contacting surfaces of the adjunct.

[0211] Referring back FIGS. 9A-9B As described above, the Schwarz-P structure 810 has a non-planar outer surface that forms an arcuate side 821 that extends between the connection interfaces 826 of the unit cells 810. Thus, when the Schwarz-P structure 810 is interconnected to form an adjunct such as the adjunct 800 in FIGS. 8A-8F , the tissue-contacting surfaces can form tissue-contacting surfaces 802 having planar and non-planar surfaces, as in FIGS. 8A-8B . This is a result of the structural configuration of at least the top portion 812 of each unit cell 810 (e.g., the exposed topmost outer surface 827a and the arcuate side 821 of the top portion 812) and their spaced apart relationship from one another. Thus, the edge conditions of the adjunct can be minimized by applying an outer layer having a substantially planar (e.g., planar within manufacturing tolerances) geometry positioned on at least one additional tissue-contacting surface of the adjunct, such as the tissue-contacting surfaces 802 of the adjunct 800 in FIGS. 8A-8F . Thus, this can reduce the tissue load (applied stress) on the adjunct during placement of the stapling device. Additionally, this can simplify the attachment requirements between the adjunct and the cartridge.

[0212] While the outer layer can have various configurations, in some embodiments, the outer layer can be formed from one or more planar arrays of struts (e.g., a planar array of struts 1706 and a planar array of struts 1708 of the first lattice structure 1702 of the exemplary adjunct 1700 shown in FIGS. 17A-17C ) while in other embodiments, the outer layer can be in the form of a film (e.g., a film 1706 of the first lattice structure 1702 of the exemplary adjunct 1700 shown in FIG. 18 ).

[0213] FIGS. 17A-17C An exemplary adjunct 1700 having a first lattice structure 1702 formed from interconnected repeating unit cells 1704 and at least one planar array of struts 1706, 1708 is shown. Each unit cell 1704 is similar to the unit cell 1704 of the first lattice structure 1702 of the exemplary adjunct 1700 shown in FIGS. 9A-9Band thus common features are not described in detail herein. In this illustrated embodiment, there are two planar arrays 1706, 1708, with the first planar array 1706 extending across a top tissue-facing surface 1712 of the first lattice structure 1702 (e.g., in the YZ plane) and the second planar array 1706 extending across at least one side tissue-facing surface 1714 of the first lattice structure 1702 (e.g., in the XZ plane). In other embodiments, the first planar array 1706 or the second planar array 1708 can be omitted. In still other embodiments, the adjunct 1700 can include additional planar arrays.

[0214] While the planar arrays 1706, 1708 can have various configurations, in this illustrated embodiment, the first planar array 1706 and the second planar array 1708 each include longitudinal struts 1716 that are parallel to a longitudinal axis (L A ) of the adjunct 1700 and extend along the longitudinal axis. While not shown, it is also contemplated that additional struts can be added to the first planar array 1706 and the second planar array 1708. For example, in one embodiment, the first planar array 1706 and / or the second planar array 1708 can include cross struts that extend at an angle relative to the longitudinal axis and intersect the first longitudinal struts and / or the second longitudinal struts (e.g., thereby creating a repeating X pattern).

[0215] In use, when the adjunct 1700 is releasably retained on a cartridge, such as the cartridge 200 in FIGS. 1-2C , the adjunct 1700 overlaps the rows of staples disposed within the cartridge. As such, the first planar array 1706 can add to the final solid height of the adjunct 1700 and thus accelerate its densification. However, to minimize the impact of the first planar array 1706 on densification, the first planar array 1706 can be designed in a manner that it does not overlap the rows of staples. For example, as shown in FIGS. 17A-17C , the first planar array 1706 is divided into four spaced apart portions 1706a, 1706b, 1706c, 1706d such that three gaps 1718, 1720, 1722 are formed therebetween and along the longitudinal axis (L A ) of the adjunct 1700. As shown in FIG. 17C , these three gaps 1718, 1720, 1722 can coincide with three rows of staples 1724, 1726, 1728 of the cartridge (not shown) and thus the first planar array 1706 will not be captured, or minimized by staples, during deployment.

[0216] As described above, in some embodiments, the absorbable film can be positioned on at least a portion of at least one of the non-planar tissue-facing surfaces of the lattice structure to thereby substantially prevent the tissue from causing premature detachment of the adjunct from the cartridge as the tissue slides across the adjunct. That is, the absorbable film can minimize edge conditions, thereby reducing friction that would otherwise exist on the tissue-contacting surfaces of the adjunct.

[0217] FIG. 18 An exemplary embodiment of an adjunct 1800 disposed on a cartridge 1801 is shown. The adjunct 1800 includes a lattice structure 1802 having an absorbable film 1804 disposed on at least a portion thereof. Similar to the lattice structure of the adjunct 800 in FIG. 8A FIGS. 9A-9B The lattice structure 1802 of the adjunct 1800 is formed of interconnected repeating unit cells 1806, each of which is similar to the cell 810 in In other embodiments, the absorbable film is not disposed on all of the tissue-facing surfaces of the lattice structure, e.g., the first lateral side surface and / or the second lateral side surface.

[0218] The absorbable film can have a variety of configurations. For example, in some embodiments, the absorbable film is designed to have a thickness that nominally affects the densification of the adjunct under applied stress and / or when formed of one or more materials that help reduce the friction of the tissue-contacting layer for tissue manipulation. In some embodiments, the thickness of the absorbable film can be less than or equal to about 15 microns, e.g., about 5 microns to 15 microns, or about 8 microns to 11 microns. In one embodiment, the absorbable film can be formed of polydioxanone.

[0219] Attachment features

[0220] In some embodiments, the non-strut-based adjunct includes one or more attachment features that extend at least partially along a length of the adjunct and are configured to engage a staple cartridge to thereby hold the adjunct on the cartridge prior to staple deployment. The one or more attachment features can have a variety of configurations. For example, the one or more attachment features can be channel attachments FIGS. 19A-21 FIGS. 22A-22B ​) and / or end attachment FIGS. 24-25 The channel attachment is configured to engage (e.g., crimp or snap into) an elongate cut slot formed between opposing longitudinal edges in the cartridge, and the end attachment is configured to engage with a recessed end channel defined within the cartridge. The adjuncts 1900, 2000, 2100, 2200 are substantially similar to the adjunct 800 in FIGS. 8A-8F , except for the differences discussed in detail below, and thus common features are not discussed in detail herein.

[0221] In some embodiments, the channel attachment can include one or more compressible members that are structurally configured to be inserted into the longitudinal slot of the cartridge to engage the opposing walls of the longitudinal slot. In certain embodiments, the one or more compressible members can include a compressible opening extending therethrough in the longitudinal direction, e.g., along the length of the cartridge-contacting surface of the adjunct.

[0222] FIGS. 19A-19B An exemplary embodiment of an adjunct 1900 is shown that includes a channel attachment 1910 having two compressible members 1912, 1914 interconnected by at least one common elongate joint 1916. While the two compressible members 1912, 1914 can have various configurations, in this illustrated embodiment, each compressible member 1912, 1914 is in the form of an elongate rod having a triangular cross-sectional shape taken across its width (e.g., in the y-direction) with a hollow triangular channel 1912a, 1914a extending therethrough along its length (e.g., in the z-direction). As shown, the two elongate rods 1912, 1914 are interconnected at corresponding vertices, thereby forming an elongate joint 1916 that defines a central connection region having a narrow thickness (e.g., in the x-direction). As FIG. 19B shown, when the adjunct 1900 is disposed on a cartridge 1901 similar to the cartridge 200 in FIGS. 1-2C , the at least one elongate joint 1916 (and thus the central connection region) is positioned equidistant from the opposing walls 1903a, 1903b of the longitudinal slot 1903, as FIG. 19BThe central connecting region is aligned with the push line of the cutting member, and thus, due to the narrow width of the central connecting region, the risk of clogging the cutting member as it is advanced through the adjunct 1900 can be minimized or prevented. That is, the central connecting region minimizes additional adjuncts that the cutting member would otherwise cut as it is advanced through the longitudinal slot 1903. Additionally, the hollow triangular channels 1912a, 1914a reduce the amount of material on each side of the push line, which can also minimize the binding of the cutting edge of the adjunct as it is further advanced through the longitudinal slot 1903 with the cutting member.

[0223] While the total width W C may vary, in this illustrated embodiment, the total width W C is greater than the width W L (e.g., the distance between two opposing slot walls 1903a, 1903b) of the longitudinal slot 1903. Thus, as the channel attachment 1910 is inserted into the longitudinal slot 1903, the compressible members can deform and engage (e.g., compress against) the respective slot walls 1903a, 1903b due to the outward lateral force created by the hollow triangular channels 1912a, 1914a. Thus, a press fit or friction fit is created between the compressible members 1912, 1914 and the respective slot walls 1903a, 1903b of the cartridge 1901.

[0224] The channel attachment can have other configurations (e.g., shapes and / or sizes). For example, as FIG. 20 illustrated, the adjunct 2000 is similar to the adjunct 800 illustrated in FIGS. 8A-8G , except that the adjunct 2000 also includes a channel attachment 2010 in the form of an elongate tab that extends outwardly from the cartridge contact surface 2004 of the adjunct 2000 and is positioned between two inner row repeat cells 2010a, 2012a. The elongate tab 2010 is configured to be inserted into the longitudinal slot of a cartridge, such as the longitudinal slot 210 of the cartridge 200 in FIG. 2A and FIG. 2C .

[0225] While the elongate tab 2010 can have various configurations, in this illustrated embodiment, the elongate tab 2010 is formed of two compressible longitudinal rods 2010a, 2010b with a crossbar 2010c extending therebetween. In some embodiments, the width (e.g., in the y-direction) of the elongate tab 2010 is greater than the width (e.g., the distance between two opposing slot walls) of the longitudinal slot of a staple cartridge. Thus, as the elongate tab 2010 is inserted into the longitudinal slot, the compressible members of the elongate tab 2010 can deform and engage (e.g., compress against) the respective slot walls of the longitudinal slot due to the outward lateral force created by the crossbar 2010c. FIGS. 2A-2CThe longitudinal slots 210 of the cartridge 200, the two longitudinal bars are configured to engage (e.g., compress against) the opposing slot walls as a result of the outward transverse force generated by the cross bar 2010c. As a result, a press fit or friction fit is formed between the elongate protrusion 2010 and the slot walls of the cartridge.

[0226] FIG. 21 Another embodiment of an adjunct 2100 having channel attachments is shown. The adjunct 2100 is similar to the adjunct 2000 shown FIG. 20 except that the channel attachments are in the form of discrete protrusions 2110 FIG. 21 only two are shown) that are spaced apart along the longitudinal axis L A of the adjunct 2100. While the protrusions 2110 can have various configurations, in this illustrated embodiment, each protrusion 2110 is in the form of an annular boss having an oval shape. In other embodiments, the protrusions 2110 can be any other suitable shape and / or vary in size / shape relative to one another. Each annular boss 2110 can be configured to be compressible, and in some embodiments, is sized such that the width (e.g., in the y-direction) of each boss can be greater than the width of the longitudinal slot (e.g., the distance between the two opposing slot walls) of a staple cartridge, such as the longitudinal slot 210 in the staple cartridge 200 in FIGS. 2A-2C therefore, when the discrete annular bosses 2110 are inserted into the longitudinal slot of the cartridge, their outer surfaces 2110a are configured to engage (e.g., compress against) the opposing slot walls as a result of the outward radial force of the annular bosses. As a result, a press fit or friction fit is formed between the annular bosses 2110a and the slot walls of the longitudinal slot.

[0227] Alternatively or in addition thereto, in some embodiments, an adjunct can include edge attachment features configured to engage corresponding edge attachment features of the adjunct. For example, as shown in FIGS. 27-29, the edge attachment features 2200a of the adjunct 2200 are in the form of a plurality of discrete protrusions 2200b that are spaced apart along the longitudinal axis L of the adjunct 2200. While the protrusions 2200b can have various configurations, in this illustrated embodiment, each protrusion 2200b is in the form of a cylindrical post. In other embodiments, the protrusions 2200b can be any other suitable shape and / or vary in size / shape relative to one another. Each cylindrical post 2200b can be configured to be compressible, and in some embodiments, is sized such that the diameter of each post can be greater than the width of the longitudinal slot (e.g., the distance between the two opposing slot walls) of a staple cartridge, such as the longitudinal slot 210 in the staple cartridge 200 in FIGS. 22A-22CAs shown, the adjunct 2200 can include three sets of opposing clips 2202a, 2202b, 2204a, 2204b, 2206a, 2206b that each extend laterally outward and away from opposing lateral surfaces 2200a, 2200b of the adjunct 2200. While the three sets of clips 2202a, 2202b, 2204a, 2204b, 2206a, 2206b can have various configurations, in this illustrated embodiment, the three sets of clips 2202a, 2202b, 2204a, 2204b, 2206a, 2206b each have a hook-shaped configuration that engages with a corresponding edge attachment feature 2208a, 2208b, 2210a, 2210b, 2212a, 2212b of the cartridge 2201. In this illustrated embodiment, each edge attachment feature 2208a, 2208b, 2210a, 2210b, 2212a, 2212b has an inverted L-shaped configuration, resulting in a ledge (only one ledge is shown in detail) that extends laterally outward from the staple cartridge 2201. FIGS. 22B-22C

[0228] FIG. 22C The engagement of one clip 2204a of the adjunct 2200 and one ledge 2210a of the cartridge 2201 is shown. Repetitive units of the adjunct 2200 are omitted for simplicity. As shown, the inner surface 2214a of the end portion 2214 of the clip 2204 engages the outer bottom surface 2216 of the ledge 2210a, nesting (e.g., male / female engagement) a portion of the outer surface 2218 of the ledge 2210a against a corresponding portion of the inner surface 2220 of the clip 2204a. Additionally, as shown, the ledge 2210a is outwardly biased, and thus, when a portion of the outer surface 2218 of the ledge 2210a is engaged, they are pressed against a corresponding portion of the inner surface 2220a of the clip 2204a. FIG. 22C

[0229] FIGS. 23A-23B Another embodiment of an adjunct having three sets of opposing clips 2302a, 2302b (partially obscured), 2304a, 2304b (partially obscured), 2306a, 2306b (partially obscured) configured to engage a corresponding set of opposing receiving members 2308, 2310 (partially obscured), 2312, 2314 (partially obscured), 2316, 2318 (partially obscured) of a staple cartridge 2301 is shown.

[0230] In this illustrated embodiment, each clip is structurally identical and has an inverted T-shaped configuration. Additionally, as shown, each set of receiving members is structurally identical and includes two inverted L-shaped members that are spaced apart and face each other to form a t-shaped void therebetween. For example,​​FIG. 23B The engagement of one clip 2302a with its corresponding set of receiving members 2308a, 2308b is shown in greater detail. As shown, the lateral segments 2316a, 2316b (e.g., extending in the z-direction) of the clip 2302a are configured to engage with respective interior surfaces (only one interior surface 3118 shown) of each L-shaped member 2308a, 2308b, and the vertical segment 2320 (e.g., extending in the x-direction) of the clip 2302a is configured to be positioned between the two facing surfaces (only one facing surface 2322 shown) of the L-shaped members 2308a, 2308b. Thus, the vertical segment 2320 can help maintain the longitudinal alignment of the adjunct 2300 relative to the cartridge 2301 (and thus the staples (not shown) disposed therein). The vertical segment 2320 can also help prevent premature disengagement of the clip 2302a with the corresponding set of receiving members 2308a, 2308b and thus the adjunct 2300 from the cartridge 2301 during use.

[0231] Alternatively or additionally, in some embodiments, the adjunct can include end attachment features, such as opposing proximal and distal sets of bosses that are configured to engage (e.g., press fit) into corresponding proximal and distal sets of recesses defined in the staple cartridge. For example, in one embodiment, the adjunct can have rectangular bosses that are configured to engage into the rectangular recesses 2402a, 2402b, 2404a, 2404b of the proximal and distal sets of the staple cartridge 2400 in FIG. 24 In another embodiment, the adjunct can have circular bosses that are configured to engage into the circular recesses 2502a, 2502b, 2504a, 2504b of the proximal and distal sets of the staple cartridge 2500 in FIG. 25 In another embodiment, the adjunct can have circular bosses that are configured to engage into the circular recesses 2502a, 2502b, 2504a, 2504b of the proximal and distal sets of the staple cartridge 2500 in

[0232] As mentioned above, in certain embodiments, the staple cartridge can include surface features in the form of recessed channels, such as the recessed channels 216, 218, 220 shown in FIG. 2A and FIG. 2C In such embodiments, the adjunct can be designed to engage with the recessed channels to achieve a releasable attachment mechanism between the adjunct and the staple cartridge, even when the frequency of staples within a longitudinal row of staples (e.g., the number of staples per length of staple row) differs from (e.g., is greater than) the frequency of repeating cells within a corresponding longitudinal row of cells (e.g., the number of cells per length of cell row).

[0233] FIGS. 26A-26C An adjunct 2600 is shown disposed on a staple cartridge 2602, which is similar to the staple cartridge 2600 shown in FIGS. 2A-2CThe staple cartridge 200 is described in detail herein, and therefore common features are not described in detail. The staple cartridge 2602 includes staple cavities arranged in longitudinal rows 2604a, 2604b, 2604c, 2606a, 2606b, 2606c and recessed channels surrounding each staple cavity 2604a, 2604b, 2604c, 2606a, 2606b, 2606c. As shown, a first recessed channel 2608 surrounds each first staple cavity 2604a, 2606a, a second recessed channel 2610 surrounds each second staple cavity 2604b, 2606b, and a third recessed channel 2612 surrounds each third staple cavity 2604c, 2606c. The first, second, and third recessed channels each include corresponding base plates 2614, 2616, and 2618, located at a corresponding height (e.g., extending in the x-direction) from the top surface 2602a of the staple cartridge 2602. In this illustrated embodiment, the corresponding heights are the same, while in other embodiments, the corresponding heights may be different.

[0234] While the appendage 2600 may have various configurations, in this illustrated embodiment, the appendage 2600 is formed by repeating cells 2620 and attachment features 2622 extending from at least a portion of the plurality of cells 2620. Each attachment feature 2622 is configured to be inserted into and engage with at least a portion of the recessed channels 2608, 2610, 2612 of the staple cartridge 2602, thereby holding the appendage 2600 to the staple cartridge 2602 prior to staple deployment.

[0235] Although the attachment feature 2622 can have various configurations, each attachment feature has a different geometry, allowing each attachment feature to engage with a corresponding recessed channel. This difference in geometry, compared to the frequency of the staples 2605 in the staple cavities 2604a, 2604b, 2604c, 2606a, 2606b, 2606c of the staple cartridge 2602, is due to the difference in the frequency of the cell. Therefore, the attachment feature 2622 is positioned on the corresponding cell 2620 at a predetermined location corresponding to the recessed channels 2608, 2610, 2612. FIG. 26A As shown, and in FIGS. 26B-26C The image shows half (e.g., the left half) of the appendage 2600 in more detail, and the corresponding geometry of the attachment feature 2622 is configured to engage the recessed channels 2608, 2610, 2612 relative to the longitudinal axis L of the staple cartridge 2602. A The corresponding vertices 2608a, 2610a, 2610b, and 2612a point laterally outward. In other embodiments, the geometry of the attachment feature may be configured to engage other portions of the recessed channel.

[0236] The geometry of the attachment features 2622 can vary laterally and / or longitudinally relative to the longitudinal axis of the cartridge. The geometric variation depends at least on the frequency of the cells 2620 relative to the frequency of the staples 2605 and the shape of the staple cavities 2604a, 2604b, 2604c, 2606a, 2606b, 2606c. For example, the attachment features 2622 can vary in at least one of height (e.g., in the x-direction), width (e.g., in the y-direction), length (e.g., in the z-direction), and shape relative to one another. For example, as shown in FIGS. 26A and 26B, the height H1 of the first attachment feature 2622a extending from the first repeating cell 2620a is greater than the height H2 of the second attachment feature 2622b extending from the second repeating cell 2620b, and thus the heights of the first and second attachment features 2622a, 2622b vary laterally relative to the longitudinal axis L of the cartridge 2602. FIG. 26B The width W1 of the first attachment feature 2622a extending from the first repeating cell 2620a is greater than the width W2 of the second attachment feature 2622b extending from the second repeating cell 2620b, and thus the widths of the first and second attachment features 2622a, 2622b vary laterally relative to the longitudinal axis L of the cartridge 2602. A The length L1 of the first attachment feature 2622a extending from the first repeating cell 2620a is greater than the length L2 of the second attachment feature 2622b extending from the second repeating cell 2620b, and thus the lengths of the first and second attachment features 2622a, 2622b vary laterally relative to the longitudinal axis L of the cartridge 2602. FIG. 26A The shape of the first attachment feature 2622a extending from the first repeating cell 2620a is different than the shape of the second attachment feature 2622b extending from the second repeating cell 2620b, and thus the shapes of the first and second attachment features 2622a, 2622b vary laterally relative to the longitudinal axis L of the cartridge 2602. FIG. 26B The length L1 of the first attachment feature 2622a extending from the first repeating cell 2620a is greater than the length L2 of the second attachment feature 2622b extending from the second repeating cell 2620b, and thus the lengths of the first and second attachment features 2622a, 2622b vary laterally relative to the longitudinal axis L of the cartridge 2602. A The length L1 of the first attachment feature 2622a extending from the first repeating cell 2620a is greater than the length L2 of the second attachment feature 2622b extending from the second repeating cell 2620b, and thus the lengths of the first and second attachment features 2622a, 2622b vary laterally relative to the longitudinal axis L of the cartridge 2602. A The length L1 of the first attachment feature 2622a extending from the first repeating cell 2620a is greater than the length L2 of the second attachment feature 2622b extending from the second repeating cell 2620b, and thus the lengths of the first and second attachment features 2622a, 2622b vary laterally relative to the longitudinal axis L of the cartridge 2602. FIG. 26A The length L1 of the first attachment feature 2622a extending from the first repeating cell 2620a is greater than the length L2 of the second attachment feature 2622b extending from the second repeating cell 2620b, and thus the lengths of the first and second attachment features 2622a, 2622b vary laterally relative to the longitudinal axis L of the cartridge 2602. A The length L1 of the first attachment feature 2622a extending from the first repeating cell 2620a is greater than the length L2 of the second attachment feature 2622b extending from the second repeating cell 2620b, and thus the lengths of the first and second attachment features 2622a, 2622b vary laterally relative to the longitudinal axis L of the cartridge 2602.

[0237] In certain embodiments, the lateral variation in the shape and / or height of the attachment features can correspond to a lateral variation in the recessed channel. For example, although not shown, in some embodiments, the walls of at least a portion of the recessed channel can extend at an angle relative to the longitudinal axis of the cartridge, and thus one or more of the attachment features can vary in shape and / or height to correspond to the recessed channel. In other embodiments, the length of the recessed channel can vary laterally, and one or more of the attachment features can vary in shape and / or height to correspond to the recessed channel.

[0238] Cell frequency

[0239] Non-strut-based adjuncts can vary in thickness longitudinally (e.g., along its length, e.g., in the z-direction) and / or laterally (e.g., along its width, e.g., in the y-direction). Thus, where the frequency of the staples within a longitudinal row of staples (e.g., the number of staples per length of staple row) differs from (e.g., is greater than) the frequency of repeating cells within a corresponding longitudinal row of cells (e.g., the number of cells per length of cell row), the staple leg of each staple can be advanced through different portions of the adjunct, where each portion has a different relative thickness, as shown in FIG. 27

[0240] FIG. 27 An example embodiment of a stapling assembly 2700 is shown having a staple cartridge 2702, as in FIGS. 1-2C , and having staples arranged in longitudinal rows (only four staples 2704, 2706, 2708, 2710 of a portion of a first longitudinal row of staples 2712 are shown). An adjunct 2714 is disposed on a top surface 2702a of the staple cartridge 2702. The adjunct 2714 includes interconnected repeating non-strut cells arranged in longitudinal rows (only a portion of a first longitudinal row of cells 2717 is shown), as in FIGS. 8A-9B . As shown, the first longitudinal row of cells 2717 overlaps the first longitudinal row of staples 2712, and the frequency of the staples 2704, 2706, 2708, 2710 differs from the frequency of the cells 2716a, 2716b, 2716c, 2716d, 2716e (e.g., non-multiple). Thus, for example, when the adjunct 2714 is stapled to tissue, each staple leg 2704b, 2706a, 2706b, 2708a, 2708b, 2710a of the corresponding staple 2704, 2706, 2708, 2710 aligns with, and thus will penetrate, a different respective portion 2718, 2720, 2722, 2724, 2726 of the first longitudinal row of cells 2712 (and thus the adjunct 2714), and the thickness of the adjunct 2714 captured within the firing staple will vary between adjacent staples stapled to uniform tissue. FIG. 27 As shown, due to the structural configuration of the repeating cells 2716a, 2716b, 2716c, 2716d, 2716e (e.g., not generally square), at least two or more of these different portions 2718, 2720, 2722, 2724, 2726, 2728 can have different relative thicknesses T1, T2, T3, T4, T5 (e.g., thick and thin thicknesses), and thus the thickness of the adjunct 2714 captured within the firing staple will vary between adjacent staples stapled to uniform tissue.

[0241] ​In some embodiments, the difference in relative thickness of the adjunct can be paired with a corresponding difference in staple leg length. For example, when the staple and cell frequency are the same, the length of the leg of any staple configured to be advanced through a thicker portion of the adjunct can be longer than the leg of any staple configured to be advanced through a thinner portion of the adjunct. Alternatively or additionally, the difference in relative thickness can be paired with a corresponding difference in anvil pocket depth, or, if the staple drivers are at the same height, a difference in tissue gap between the first staple leg to the second staple leg, if the staple drivers are at the same height.

[0242] FIG. 28A An exemplary embodiment of a stapling assembly 2800 similar to the stapling assembly 2700 in FIG. 27 is shown, except that the structural configuration of the adjunct 2801 has been modified such that the staple frequency and cell frequency are the same. Thus, the first staple leg 2804a, 2806a, 2808a of each staple 2804, 2806, 2808 is configured to pass through a respective portion of the adjunct having the same first thickness T1, and the second staple leg 2804b, 2806b, 2808b of each staple 2804, 2806, 2808 is configured to pass through a respective portion of the adjunct 2801 having the same second thickness T2. As shown, the first thickness T1 is greater than the second thickness T2, and thus to offset the difference in thickness, the first leg length L1 of each staple 2804, 2806, 2808 can be greater than the second leg length L2. In this illustrated embodiment, the crown 2804c, 2806c, 2808c of each staple 2804, 2806, 2808 has a non-planar configuration (e.g., a stepped configuration) to achieve the difference in staple leg length. Additionally, when the staples 2804, 2806, 2808 are deployed and the adjunct 2801 is stapled to tissue T, each staple will have two different formed staple heights H1, H2, as shown in FIG. 28B . FIG. 29 Another exemplary embodiment of a stapling assembly 2900 similar to the stapling assembly 2800 is shown, except that the crown 2904c, 2906c, 2908c of each staple 2904, 2906, 2908 is generally planar (e.g., generally straight or linear within manufacturing tolerances), and thus, the formed staple height of the first staple will be generally uniform (e.g., nominally the same within manufacturing tolerances).

[0243] Strut-based adjunct

[0244] As noted above, the adjunct can include a lattice structure formed of strut-based unit cells (e.g., defined by planar interconnecting struts). Generally, such adjuncts can include a tissue-contacting layer, a reservoir-contacting layer, and an internal structure (e.g., a buckling structure). The internal structure generally includes struts (e.g., spacing struts) that connect the tissue-contacting layer and the reservoir-contacting layer in a spaced-apart relationship. These struts can be configured to collapse without contacting one another when the adjunct is compressed under stress. Thus, densification of the adjunct can be delayed, and thus can occur at higher strains.

[0245] The tissue-contacting layer and the reservoir-contacting layer can have various configurations. In some embodiments, at least one of the tissue-contacting layer and the reservoir-contacting layer can include a plurality of struts defining openings. In some embodiments, both the tissue-contacting layer and the reservoir-contacting layer are generally planar (e.g., planar within manufacturing tolerances). The tissue-contacting layer and the reservoir-contacting layer can be oriented parallel to one another along a longitudinal axis extending from a first end to a second end of the adjunct, and can further define a vertical axis extending therebetween.

[0246] The struts can have various configurations. For example, in some embodiments, the struts can have a generally uniform (uniform within manufacturing tolerances) cross-section, while in other embodiments, the struts can have different cross-sections. In some embodiments, the adjunct can have an average strut thickness in a range of about 0.1 mm to 0.5 mm, about 0.1 mm to 0.4 mm, or about 0.1 mm to 0.3 mm.

[0247] FIGS. 30A-30B An exemplary strut-based adjunct 3000 is shown. The adjunct 3000 includes a tissue-contacting layer 3002, a reservoir-contacting layer 3004, and an internal structure 3006 extending therebetween. The internal structure 3006 is configured to collapse (compress) when the adjunct 3000 is under applied stress, and thus cause the adjunct 3000 to compress when stapled to tissue.

[0248] While the tissue-contacting layer 3002 and the reservoir-contacting layer 3004 can have various configurations, in this illustrated embodiment, they are both generally planar (e.g., planar within manufacturing tolerances). Additionally, the tissue-contacting layer 3002 and the reservoir-contacting layer 3004 are parallel to one another along a longitudinal axis (L A ) extending from a first end 3000a to a second end 3000b of the adjunct 3000. As shown, the tissue-contacting layer 3002 and the reservoir-contacting layer 3004 are inverted images of one another, with the thickness (T C ) of the reservoir-contacting layer 3004 being greater than the thickness (T T). Thus, for simplicity, the following description is with respect to the tissue contact layer 3002. However, those skilled in the art will appreciate that the following discussion also applies to the reservoir contact layer 3004.

[0249] The tissue contact layer 3002 has a first longitudinal strut 3008a, a second longitudinal strut 3010a, and a third longitudinal strut 3012a extending along a longitudinal axis (L) of the appendage 3000, with the second longitudinal strut 3010a positioned between but spaced apart from the first longitudinal strut 3008a and the third longitudinal strut 3012a. The tissue contact layer 3002 also includes first cross struts 3014a and second cross struts 3016a. Each of the first cross struts 3014a is connected to the first longitudinal strut 3008a and the second longitudinal strut 3010a. While the first cross struts 3014a can be oriented at a variety of different positions, in the illustrated embodiment, the first cross struts 3014a are oriented orthogonally relative to the first longitudinal strut 3008a and the second longitudinal strut 3010a. Similarly, each of the second cross struts 3016a is connected to the second longitudinal strut 3010a and the third longitudinal strut 3012a. While the second cross struts 3016a can be oriented at a variety of different positions, in the illustrated embodiment, the second cross struts 3016a are oriented orthogonally relative to the second longitudinal strut 3010a and the third longitudinal strut 3012a. Additionally, as shown, the first cross struts 3014a are aligned with the second cross struts 3016a in the y-direction.

[0250] Additionally, the first cross struts 3014a are longitudinally spaced apart from one another at a first distance Dl, and the second cross struts are longitudinally spaced apart from one another at a second distance D2. Thus, openings 3018a are created within the tissue contact layer 3002. While the openings 3018a can have a variety of sizes and shapes, in the illustrated embodiment, Dl and D2 are the same or substantially the same, and thus, in combination with the orientation of the first cross struts 3014a and the second cross struts 3016a, the resulting openings 3018a are in the form of rectangles having a generally uniform size (e.g., nominally the same within manufacturing tolerances).

[0251] While the internal structure 3006 can have various configurations, in this illustrated embodiment, the internal structure 3006 includes spaced struts 3020 extending between the tissue contact layer 3002 and the cartridge contact layer 3004. The spaced struts 3020 include a first set of angled struts 3022a, 3022b and a second set of angled struts 3024a, 3024b, each of which extends at an angle (e.g., 45 degrees) relative to the tissue contact layer 3002 and the cartridge contact layer 3004. The first set of angled struts includes a first angled strut 3022a extending from a first longitudinal strut 3008a of the tissue contact surface 3002 to a second longitudinal strut 3010b of the cartridge contact layer 3004, and a second angled strut 3022b extending from a first longitudinal strut 3008b of the cartridge contact layer 3004 to a second longitudinal strut 3010a of the tissue contact layer 3002. Thus, the first angled strut 3022a and the second angled strut 3022b alternate along the length (L) of the adjunct. The second set of alternating angled struts includes a third angled strut 3024a and a fourth angled strut 3024b. The third angled strut 3024a is similar to the first angled strut 3022a, except that the third angled strut 3024a extends from the second longitudinal strut 3010a of the tissue contact layer 3002 to a third longitudinal strut 3012b of the cartridge contact layer 3004. The fourth angled strut 3024b is similar to the second angled strut 3022b, except that the fourth angled strut 3024b extends from the second longitudinal strut 3010b of the cartridge contact layer 3004 to the third longitudinal strut 3012a of the tissue contact layer 3002. Thus, in this illustrated embodiment, the first angled strut 3022a and the third angled strut 3024a extend in the same direction relative to each other, and the second angled strut 3022b and the fourth angled strut 3024b extend in the same direction relative to each other.

[0252] As FIG. 30A Further shown, the openings 3018b are created within the cartridge contact layer 3004 between the first cross strut 3014b and the second cross strut 3016b. In addition, the angled struts 3022a, 3022b, 3024a, 3024b substantially overlap the corresponding openings 3018b in at least the cartridge contact layer 3004, and as described above, the cartridge contact layer 3004 has a thickness T T C ​Accordingly, the openings 3018b defined in the pocket contact layer 3004 can be configured to receive at least a portion of the corresponding angled struts as the adjunct 3000 bends when compressed under applied stress. This creates additional space within the internal structure 3006 for buckling, and thus reduces the solid height of the adjunct 3000. Accordingly, in use, densification of the adjunct 3000 can be delayed such that the adjunct 3000 can experience a wider range of deformation without reaching its solid height.

[0253] Additionally, by alternating the angled struts 3022a, 3022b, 3024a, 3024b, a concentration zone 3030 within the internal structure 3006 is created. As shown, this concentration zone 3030 extends in the longitudinal direction along the adjunct between the first and second sets of angled struts 3022a, 3022b, 3024a, 3024b. Accordingly, no struts 3020 within the internal structure 3006 overlap this concentration zone 3030, as shown in more detail in FIG. 30B FIG. 3B. In other words, this concentration zone 3030 is designed to be a strut-free space in which no struts cross into the space prior to or during compression of the adjunct. Accordingly, the presence of this concentration zone 3030 can increase the point of densification of the adjunct 3000 while suturing the adjunct to tissue (e.g., reducing the solid height of the adjunct). Additionally, the concentration zone can overlap the cut line of the adjunct, thus the amount of material along the cut line can be reduced. This can help facilitate advancement of the cutting element of the suturing device, and thus make cutting of the adjunct easier.

[0254] FIG. 31A , FIG. 32A , FIG. 33A and FIG. 34A Various other example strut-based adjuncts 3100, 3200, 3300, and 3400 are shown. Each example adjunct has a lattice structure formed of repeating interconnected strut-based unit cells that are FIGS. 31B-31D , FIGS. 32B-32D , FIGS. 33B-33E and FIGS. 34B-34E are shown in more detail in FIGS. 31A-34B. These adjuncts are structured so as to compress when exposed to compressive forces (e.g., stress applied when sutured to tissue).

[0255] FIG. 31AAnother exemplary appendage 3100 in the form of a lattice structure is shown, comprising a top portion 3102, a bottom portion 3104, and an internal structure 3106 extending therebetween. The top portion 3102 is configured to contact tissue and thus form a tissue contact layer of the appendage 3100, while the bottom portion 3104 is configured to attach to a compartment and thus form a compartment contact layer of the appendage 3100. The internal structure 3106 may be configured, for example, to be compressible into a deformable state under load when sutured to tissue. The lattice is formed by an array of repeating cells 3110, one of which is in... FIGS. 31B-31D The details are shown in more detail below. Therefore, for simplicity, the following description concerns the top portion 3102, the bottom portion 3104, and the internal structure 3106 of a cell.

[0256] While the top portion 3102 and the bottom portion 3104 can have various configurations, in this illustrated embodiment, the top portion 3102 and the bottom portion 3104 are inverted images of each other, and therefore, for simplicity, the following description pertains to the top portion 3102 of a cell 3110. However, those skilled in the art will understand that the following discussion also applies to the bottom portion 3104.

[0257] like FIGS. 31A-31D As shown, the top portion 3102 includes a first cross brace 3112 and a second cross brace 3114, and a first angled brace 3116 and a second angled brace 3118 extending therebetween. In this illustrated embodiment, the first angled brace 3116 extends at a first angle from a first end of the first cross brace 3112 and terminates at a middle portion of the second cross brace 3114, and the second angled brace 3118 extends at a second angle from a second opposite end of the first cross brace 3112 and terminates at a middle portion of the second cross brace 3114. Thus, the first angled brace 3116 and the second angled brace 3118 converge and connect at a central segment 3114a of the second cross brace 3114. In other embodiments, the first angled brace 3116 and the second angled brace 3118 may extend at any other suitable angle.

[0258] While the internal structure 3106 can have various configurations, in this illustrated embodiment, the internal structure 3106 includes three spacer struts 3120a, 3120b, and 3120c. For example... FIGS. 31B-31DAs shown, the first spacer 3120a and the third spacer 3120c each interconnect the first cross support 3112 of the top portion 3102 to the first cross support 3112 of the bottom portion 3104, and the second spacer 3120b interconnects the center segment 3114a of the second cross support 3114 of the top portion 3102 to the center segment 3114a of the second cross support 3114 of the bottom portion 3104.

[0259] FIG. 32A Another exemplary appendage 3200 in the form of a grid structure is shown, the grid structure including a top portion 3202, a bottom portion 3204, and an internal structure 3206 extending therebetween. The top portion 3202 is configured to contact tissue and thus form a tissue contact layer of the appendage 3200, while the bottom portion 3204 is configured to attach to a compartment and thus form a compartment contact layer of the appendage 3200. Except for the differences described below, the appendage 3200 is similar to... FIG. 31A As shown in 31D, the appendage 3100. The grid is formed by an array of repeating cells 3201, where one of the repeating cells is in... FIGS. 32B-32D The following is shown in more detail. Therefore, for simplicity, the following description concerns the top portion 3202, the bottom portion 3204, and the internal structure 3206 of a cell.

[0260] like FIGS. 32B-32D As shown, the top portion 3202 is offset from the bottom portion 3204 in the first and second dimensions (X, Z). The top portion 3202 includes two separate sets of interconnecting struts 3202a, 3202b, which are connected to each other by connecting struts 3203. The bottom portion 3204 includes eight interconnecting struts 3204a, six of which form the first hexagonal face of cell 3201. The internal structure 3206 includes two sets of spacer struts 3208a, 3208b, 3208c, 3210a, 3210b, 3210c extending from the top portion 3202 to the bottom portion, thereby forming two additional hexagonal faces of cell 3201, as shown. FIG. 32B As shown.

[0261] FIG. 33A Another exemplary appendage 3300 in the form of a lattice structure is shown, comprising a top portion 3302, a bottom portion 3304, and an internal structure 3306 extending therebetween. The top portion 3302 is configured to contact tissue and thus forms a tissue contact layer of the appendage 3300, while the bottom portion 3304 is configured to attach to a compartment of a surgical suture device and thus forms a compartment contact layer of the appendage 3300. Except for the differences described below, the appendage 3300 is similar to... FIG. 31AAs shown in 31D, the appendix 3100. The grid is formed by an array of repeating cells 3310, where one of the repeating cells is in... FIGS. 33B-33E The details are shown in more detail below. Therefore, for simplicity, the following description concerns the top portion 3302, the bottom portion 3304, and the internal structure 3306 of a cell 3310.

[0262] While the top portion 3302 and the bottom portion 3304 can have various configurations, in this illustrated embodiment, the top portion 3302 and the bottom portion 3304 are substantially identical to each other, and therefore, for simplicity, the following description pertains to the top portion 3302 of a cell 3310. However, those skilled in the art will understand that the following discussion also applies to the bottom portion 3304.

[0263] like FIGS. 33A-33E As shown, the top portion 3302 includes a first pair of opposing outer struts 3312a, 3312b and a second pair of opposing outer struts 3312c, 3312d. The first and second pairs of outer struts 3312a, 3312b, 3312c, 3312d are connected in the form of a parallelogram having four corners 3316a, 3316b, 3316c, 3316d. In this illustrated embodiment, the parallelogram is a square. The top portion 3302 also includes a first cross strut 3318 connecting the first pair of opposing outer struts 3312a, 3312b and a second cross strut 3320 connecting the second pair of opposing outer struts 3312c, 3312d. As shown, the first cross strut 3318 and the second cross strut 3320 intersect each other at a 90-degree angle at the middle of the top portion 3302.

[0264] Although the internal structure 3306 can have various configurations, in this illustrated embodiment, the internal structure 3306 includes a first side 3322a, a second adjacent side 3322b, a third side 3322c opposite to the first side 3322a, and a fourth side 3322d opposite to the second side 3322b (see [link to previous embodiment]). FIG. 33D Although each side may have various configurations, in this illustrated embodiment, the first side 3322a and the third side 3322c are substantially the same as each other, and the second side 3322 and the fourth side 3322d are substantially the same as each other.

[0265] like FIGS. 33B-33EAs shown, the first side 3322a of the interior structure 3306 includes a first angled spacer 3324a and a second angled spacer 3324b that extend in opposite directions from a center segment 3313 of the outer side strut 3312a of the bottom portion 3304 to the first corner 3316a and the second corner 3316b of the top portion 3302, respectively. Similarly, the third side 3322c of the interior structure includes a third angled spacer 3326a and a fourth angled spacer 3326b that extend in opposite directions from a center segment (obscured) of the outer side strut 3312b (obscured) of the bottom portion 3304 to the third corner 3316c and the fourth corner 3316c of the top portion 3302, respectively.

[0266] Additionally, the second side 3322b of the interior structure 3306 includes a fifth angled spacer 3328a and a sixth angled spacer 3328b that extend in opposite directions from a center segment 3315 of the outer side strut 3312c of the top portion 3302 to the first corner 3316a and the fourth corner 3316d of the bottom portion 3304, respectively. Similarly, the fourth side 3322d of the interior structure 3306 includes a seventh spacer 3330a and an eighth angled spacer (obscured) that extend in opposite directions from a center segment 3317 of the outer side strut 3312d of the top portion 3302 to the second corner 3316b and the third corner (third corner of the bottom portion 3304 is obscured) of the bottom portion 3304, respectively.

[0267] The interior structure 3306 also includes a first pair of angled spacers 3332a, 3332b. The first angled spacer 3332a extends from the middle of the top portion 3302 to a center segment 3334 of the outer side strut 3312c of the bottom portion 3304. Similarly, the second spacer 3332b extends from the middle of the top portion 3302 to a center segment (obscured) of the outer side strut 3312d of the bottom portion 3304. Thus, the first pair of angled spacers 3332a, 3332b extend in opposite directions from the middle of the top portion 3302.

[0268] Additionally, the internal structure 3306 includes a second pair of angled spacer struts 3336a, 3336b. The first angled spacer strut 3336a extends from the middle of the bottom portion 3304 to the center segment 3338 of the outboard strut 3312b of the top portion 3302. Similarly, the second spacer strut 3336b extends from the middle of the bottom portion 3304 to the center segment (obscured) of the outboard strut 3312a of the top portion 3302. Thus, the second pair of angled spacer struts 3336a, 3336b extend from the middle of the bottom portion 3304 in opposite directions.

[0269] FIG. 34A Another example adjunct 3400 is shown in the form of a lattice structure that includes a top portion 3402, a bottom portion 3404, and an internal structure 3406 extending therebetween. The top portion 3402 is configured to contact tissue and thus forms a tissue-contacting layer of the adjunct 3400, while the bottom portion 3404 is configured to attach to a cartridge of a surgical stapler and thus forms a cartridge-contacting layer of the adjunct 3400. The adjunct 3400 is similar to the adjunct 3100, except for the differences described below. FIG. 31A to the adjunct 3100 as shown in FIG. 31D. The lattice is formed from an array of repeating cells 3410, one of which is shown in greater detail in FIG. 31E. Thus, for simplicity, the following description is with respect to the top portion 3402, the bottom portion 3404, and the internal structure 3406 of one cell 3410. FIGS. 34B-34E Thus, for simplicity, the following description is with respect to the top portion 3402, the bottom portion 3404, and the internal structure 3406 of one cell 3410.

[0270] While the top portion 3402 and the bottom portion 3404 can have various configurations, in this illustrated embodiment, the top portion 3402 and the bottom portion 3404 are substantially identical to each other and thus, for simplicity, the following description is with respect to the top portion 3402 of one cell 3410. However, those skilled in the art will understand that the following discussion applies to the bottom portion 3404 as well.

[0271] As shown in FIG. 31E, the top portion 3402 includes a plurality of struts 3412 that are arranged in a pattern of hexagons. The internal structure 3406 includes a plurality of struts 3414 that are arranged in a pattern of hexagons. The bottom portion 3404 includes a plurality of struts 3416 that are arranged in a pattern of hexagons. FIGS. 34B-34EAs shown, the top portion 3402 includes four intersecting braces 3408a, 3408b, 3408c, and 3408d connected together at the middle of the top portion 3402. While the four intersecting braces 3408a, 3408b, 3408c, and 3408d can be connected relative to each other at different angles, in this illustrated embodiment, the four intersecting braces 3408a, 3408b, 3408c, and 3408d are connected relative to each other at 90 degrees, thus forming a cross shape with four outer ends 3411a, 3411b, 3411c, and 3411d. The top portion 3402 also includes four braces 3412a, 3412b, 3412c, and 3412d connected in a manner that forms a square with four corners 3414a, 3414b, 3414c, and 3414d. Each square strut 3412a, 3412b, 3412c, 3412d and the central segments 3416a, 3416b, 3416c, 3416d of one of the four cross-shaped struts 3408a, 3408b, 3408c, 3408d (see...) FIG. 34D )intersect.

[0272] While the internal structure 3406 can have various configurations, in this illustrated embodiment, the internal structure 3406 includes four sets of angled outer support bars, wherein each set of angled outer support bars includes two angled support bars 3418a, 3418b, 3420a, 3420b, 3422a, 3422b, 3424a, and 3424b. The four sets of angled outer support bars can have various configurations. As shown in the figure, in this illustrated embodiment, the first and second sets of outer support bars are mirror images of each other, and the third and fourth sets of outer support bars are also mirror images of each other.

[0273] like FIG. 34B As shown, the first angled support bar 3418a and the second angled support bar 3418b of the outer support bar of the first composition angle each extend in opposite directions from the first corner 3414a of the square of the bottom portion 3404 to one of the first corner 3411a and the second corner 3411b of the intersection of the top portion 3402. Similarly, the first angled support bar 3420a and the second angled support bar 3420b of the outer support bar of the second composition angle each extend in opposite directions from the third corner 3414c (obscured) of the square of the bottom portion 3404 to the remaining corners of the intersection of the top portion 3402 (e.g., the third corner 3411c and the fourth corner 3411d, respectively).

[0274] like FIG. 34BFurther shown, the first angled strut 3422a and the second angled strut 3422b of the third set of angled outer struts each extend in opposite directions from the square second corner 3414b of the top portion 3404 to one of the cross-shaped second corner 3411b and the third corner 3411c of the bottom portion 3404, respectively. Similarly, the first angled strut 3424a and the second angled strut 3424b of the fourth set of angled outer struts each extend in opposite directions from the square fourth corner 3414d of the top portion 3404 to one of the cross-shaped first corner 3411a and the fourth corner 3411d (obscured) of the bottom portion 3404, respectively.

[0275] The internal structure 3406 also includes two sets of angled inner struts, with each set including two angled struts 3426a, 3426b, 3428a, 3428b. The two sets of angled inner struts can have various configurations. As FIG. 34B shown, the first angled strut 3426a and the second angled strut 3426b of the first set of angled inner struts each extend in opposite directions from the cross-shaped middle of the top portion 3402 to one of the square second corner 3414b and the fourth corner 3414d (obscured) of the bottom portion 3404. In this illustrated embodiment, the first angled strut 3428a and the second angled strut 3428b of the second set of angled inner struts are reversed from the first angled strut 3426a and the second angled strut 3426b. That is, as FIG. 34B shown, the first angled strut 3428a and the second angled strut 3428b of the second set of angled inner struts each extend in opposite directions from the square middle of the bottom portion 3404 to one of the square first corner 3414a and the third corner 3414c (obscured) of the top portion 3402.

[0276] As FIGS. 30A-34E shown, the strut-based configuration of the adjunct creates a plurality of openings throughout the adjunct, thereby creating fewer barriers to cell infiltration as compared to non-strut-based adjunct configurations. That is, when the adjunct is sutured to tissue, these plurality of openings can allow cells to flow more quickly into the adjunct. This increased rate of the adjunct can thereby enhance the rate of tissue ingrowth as compared to other adjuncts.

[0277] While FIGS. 31A-34EThe openings in the top and bottom portions of the appendage shown are regular and symmetrically defined by struts; however, in other embodiments, the top and bottom portions may instead be planar sheets (e.g., “Swiss cheese” type sheets) in which regular or irregular openings are formed, or non-planar sheets (e.g., corrugated or wavy) in which regular or irregular openings are formed. These openings in both planar and non-planar appendage configurations can also promote inward cell growth within the appendage when the appendage is sutured to tissue.

[0278] In other embodiments, the repeating units based on the strut appendages may have other structural configurations. For example, FIG. 35 An exemplary support bar-based cell 3500 is shown that can be used to form the appendage described herein. Cell 3500 includes a top portion 3502, a bottom portion 3504, and an inner portion 3506 extending therebetween.

[0279] While the top portion 3502 and the bottom portion 3504 may have various configurations, in this illustrated embodiment, the top portion 3502 and the bottom portion 3504 are substantially identical to each other, and therefore, for simplicity, the following description pertains to the top portion 3502. However, those skilled in the art will understand that the following discussion also applies to the bottom portion 3504.

[0280] like FIG. 35 As shown, the top portion 3502 includes a first pair of opposing outer struts 3512a, 3512b and a second pair of opposing outer struts 3514a, 3514b. The first and second pairs of outer struts 3512a, 3512b, 3514a, 3514b are connected in the form of a parallelogram having four corners 3516a, 3516b, 3516c, 3516d. In this illustrated embodiment, the parallelogram is a square. The top portion 3502 also includes a first cross strut 3518 connecting the first pair of opposing outer struts 3512a, 3512b and a second cross strut 3520 connecting the second pair of opposing outer struts 3514a, 3514b. As shown, the first cross strut 3518 and the second cross strut 3520 intersect each other at a 90-degree angle at the middle of the top portion 3502.

[0281] While the interior structure 3506 can have various configurations, in the illustrated embodiment, the interior structure 3506 includes a first side 3522a, a second, adjacent side 3522b, and a third side 3522c opposite the second side 3522b, and a fourth side 3522d opposite the first side 3522a. While each side can have various configurations, in the illustrated embodiment, the first side 3522a, the second side 3522b, the third side 3522c, and the fourth side 3522d are different. In the illustrated embodiment, the fourth side 3522d does not include any spacer struts.

[0282] As shown, the first side 3522a of the interior structure 3506 includes a first angled spacer strut 3524a and a second angled spacer strut 3524b extending parallel to each other. The first angled spacer strut 3524a extends from the first corner 3516a of the bottom portion 3504 to the center segment 3513a of the first outer strut 3512a of the top portion 3502, and the second angled spacer strut extends from the center segment 3513b of the first outer strut 3512a of the bottom portion 3504 to the second corner 3516b of the top portion 3502. FIG. 35

[0283] The second side 3522b of the interior structure 3506 includes a third angled spacer strut 3526a and a fourth angled spacer strut 3526b extending parallel to each other. The third angled spacer strut 3526c extends from the second corner 3516b of the bottom portion 3504 to the center segment 3515 of the second outer strut 3514b of the top portion 3502, and the fourth angled spacer strut 3526b extends from the center segment of the second outer strut (obscured) of the bottom portion 3504 to the third corner 3516c of the top portion 3502.

[0284] Additionally, the third side 3522c of the interior structure 3506 includes a fifth angled spacer strut 3528a and a sixth angled spacer strut 3528b extending parallel to each other. The fifth angled spacer strut 3528a extends from the fourth corner 3516d of the bottom portion 3504 to the center segment 3517 of the second outer strut 3514a of the top portion 3502, and the sixth angled spacer strut 3528b extends from the center segment 3517 of the first outer strut 3514a of the bottom portion 3504 to the first corner 3516a of the top portion 3502.

[0285] ​The internal structure 3506 also includes two sets of internal angled struts. The first set includes three internal angled struts 3530a, 3530b, 3530c each extending from the middle of the top portion 3502 to the center segments 3513, 3517, 3519 of the outboard struts 3512a, 3514a, 3512b of the bottom portion 3504, respectively. Thus, in the first set, the first and third internal angled struts 3530a, 3530c extend in opposite directions, and the second internal angled strut 3530b extends in a different direction relative to the first and third internal angled struts 3530a, 3530c. The second set includes three internal angled struts 3532a, 3532b, 3532c each extending from the middle of the bottom portion 3504 to the center segments 3513, 3515, 3519 of the outboard struts 3512a, 3514b, 3512b of the top portion 3502, respectively. Thus, in the second set, the first and third internal angled struts 3532a, 3532c extend in opposite directions, and the second internal angled strut 3532b extends in a different direction relative to the first and third internal angled struts 3532a, 3532b.

[0286] In other embodiments, the repeating unit of a strut-based adjunct can have other structural configurations. For example, FIG. 36 An exemplary strut-based unit cell 3600 that can be used to form adjuncts described herein is shown. The unit cell 3600 includes a top portion 3602, a bottom portion 3604, and an internal portion 3606 extending therebetween.

[0287] While the top portion 3602 and the bottom portion 3604 can have various configurations, in this illustrated embodiment, the top portion 3602 and the bottom portion 3604 are substantially identical to each other, and thus, for simplicity, the following description is with respect to the top portion 3602. In embodiments, the bottom portion 3604 is an inverted image of the top portion 3602. However, those skilled in the art will appreciate that the following discussion also applies to the bottom portion 3604.

[0288] As FIG. 36As shown, the top portion 3602 includes a first pair of cross braces 3612a, 3612b and a second pair of cross braces 3612c, 3612d. The first and second pairs of cross braces 3612a, 3612b, 3612c, 3612d are connected in such a manner that the top portion 3602 is in the form of a sparse tetrahedron with five corners 3616a, 3616b, 3616c, 3616d, 3616e. The first pair of cross braces 3612a, 3612b intersect at point 3617 on the top portion. Cross brace 3612a connects to cross brace 3612c at corner 3616d, and cross brace 3612b connects to cross brace 3612d at corner 3616c. As shown in the figure, the cross braces 3612a and 3612b intersect each other at a 90-degree angle at the intersection point 3617 in the middle of the top portion 3602.

[0289] like FIG. 36 As shown, the internal structure 3606 includes a first angled spacer 3620a and a second angled spacer 3620b extending parallel to each other. The first angled spacer 3620a extends from a first corner 3616a of the top portion 3602 to a corner 3616e of the bottom portion 3604, and the second angled spacer 3620b extends from a third corner 3616c of the top portion 3602 to the intersection point 3617 of the bottom portion 3604. Additionally, the internal structure 3606 includes a third angled spacer 3622a and a fourth angled spacer 3622b extending parallel to each other. The third angled spacer 3622a extends from the second corner 3616b of the top portion 3602 to the corner 3616e of the bottom portion 3604, and the fourth angled spacer 3622b extends from the fourth corner 3616d of the top portion 3602 to the intersection point 3617 of the bottom portion 3604. Therefore, the first angled spacer 3620a and the third angled spacer 3622a extend in opposite directions, and the second angled spacer 3620b and the fourth angled spacer 3622b extend in opposite directions.

[0290] Outer layer

[0291] In some embodiments, the adjunct can include a lattice structure (e.g., a first lattice structure or an internal lattice structure) extending from the top surface to the bottom surface and at least one outer layer, each outer layer having a different compression ratio (e.g., a ratio of pre-compression height to compression height). Thus, the compression characteristics of the lattice structure and the at least one outer layer are different and, as a result, can be tailored to perform different functions (e.g., tissue ingrowth, cartridge attachment, etc.) while also, in combination, achieving a total compression profile of the adjunct that is desirable for varying staple conditions and / or staple heights. For example, based on the total compression profile of the resulting adjunct, the adjunct is configured to experience a strain in a range of about 0.1 kPa to 0.9 kPa when under an applied stress in a range of about 30 kPa to 90 kPa. In other embodiments, the strain can be in a range of about 0.1 to 0.8, about 0.1 to 0.7, about 0.1 to 0.6, about 0.2 to 0.8, about 0.2 to 0.7, about 0.3 to 0.7, about 0.3 to 0.8, about 0.3 to 0.9, about 0.4 to 0.9, about 0.4 to 0.8, about 0.4 to 0.7, about 0.5 to 0.8, or about 0.5 to 0.9.

[0292] While the lattice structure and the at least one outer layer can have various configurations, in some embodiments, the compression ratio of the first lattice structure is greater than the compression ratio of the at least one outer layer. For example, in one embodiment, the first lattice structure can be configured to compress in a range of about 3 mm to 1 mm under an applied stress and, thus, its compression ratio can be 3, while at least the outer layer can be configured to compress in a range of about 2 mm to 1 mm under the same applied stress and, thus, its compression ratio can be 2.

[0293] In certain embodiments, the adjunct can include an outer layer in the form of a second lattice structure or an absorbable film positioned on at least a portion of the top surface of the first lattice structure and configured to be positioned against tissue. The outer layer can be configured to promote tissue ingrowth within the adjunct and / or create a smooth or substantially smooth tissue contact surface that can easily slide against tissue and, thus, reduce tissue loading (applied stress) on the adjunct during placement of a stapling device and / or simplify attachment requirements between the adjunct and a cartridge. Alternatively or additionally, the adjunct can include an outer layer in the form of a film or a third lattice structure positioned on at least a portion of the bottom surface of the first lattice structure and configured to be positioned against a cartridge. Thus, the outer layer can be configured to attach the adjunct to the cartridge. For example, the outer layer can be in the form of an adhesive film and / or include one or more attachment features designed to releasably mate with a staple cartridge. In certain embodiments, the compression ratio of the lattice structure is greater than the compression ratio of the at least one outer layer.

[0294] FIGS. 37A-37B An exemplary embodiment of an adjunct 3700 disposed on a cartridge 3800 is shown. The cartridge 3800 is similar to the cartridge 200 in FIGS. 1-2C and thus common features are not described in detail herein. The adjunct 3700 includes an inner lattice structure 3702 and two outer layers 3704, 3710 each having a different compression ratio relative to one another. The inner lattice structure 3702 is generally formed from interconnected repeating cells, and when the repeating cells are omitted from this illustration, any of the repeating cells disclosed herein can be used, e.g., a strutless-based repeating cell or a strut-based repeating cell. Additionally, a first outer layer 3704 is disposed on a top surface 3702a of the inner lattice structure 3702 and is configured to contact tissue, and a second outer layer 3706 is disposed on a bottom surface 3702b of the inner lattice structure 3702 and is configured to contact the cartridge 3800.

[0295] While the first outer layer 3704 can have various configurations, in this illustrated embodiment, the first outer layer 3704 is a lattice structure formed from struts 3710 interconnected in a manner that creates hexagonal openings 3712 extending through the first outer layer 3704. These openings 3712 can be configured to promote tissue ingrowth. Those skilled in the art will appreciate that the struts can be interconnected in various other manners that will achieve openings of different sizes and shapes, and thus the lattice structure of the first outer layer is not limited to the lattice structure shown in the figures. Additionally, the first outer layer 3704 can have a lower compression ratio, and thus can be less compressible, as compared to at least the inner lattice structure 3702. Thus, when the adjunct 3700 is sutured to tissue, this can allow tissue to penetrate further into the openings 3712, and thus through the adjunct 3700, further promoting tissue ingrowth (see FIG. 38A and FIG. 38B ).

[0296] While the second outer layer 3706 can have various configurations, in this illustrated embodiment, the second outer layer 3706 is in the form of a film 3714 having protrusions 3716 extending outwardly therefrom. The protrusions 3716a, 3716b, 3716c are configured to cooperate with surface features 3802, 3804, 3806 of the cartridge 3800, as with the surface features 216, 218, 220 of the cartridge 200 in FIGS. 1-2C and FIG. 37B and FIG. 38AAs shown, this mating interaction substantially prevents slidable movement of the adjunct 3700 relative to the cartridge 3800. The shape and size of the protrusions 3716a, 3716b, 3716c, which can be triangular or diamond shaped, are complementary to the shape and size of the corresponding surface features 3802, 3804, 3806, which can be triangular or diamond shaped recessed channels. In other embodiments, the shape and size of the protrusions and surface features can differ.

[0297] Alternatively or additionally, the second outer layer 3706 can include an elongated protrusion 3730 configured to be inserted into the longitudinal slot 3808 of the cartridge 3800. While the elongated protrusion can have various configurations, in this illustrated embodiment, the elongated protrusion 3730 has a rectangular shape. In some embodiments, the elongated protrusion 3730 can extend along the entire length of the adjunct (e.g., in the z-direction), while in other embodiments, the elongated protrusion 3730 can extend along a portion of the length. In certain embodiments, the elongated protrusion 3730 can be broken up into smaller elongated discrete portions.

[0298] In other embodiments, as FIG. 39A shown, the second outer layer 3900 can include four sets of tabs 3902a, 3902b, 3904a, 3904b, 3906a, 3906b, 3908a, 3908b FIG. 39A that partially obscure 3902b, 3904b, 3906b, and 3908b), each extending outward and away from the opposing outer lateral surfaces 3900a, 3900b FIG. 39B of the second outer layer 3900. While the four sets of tabs 3902, 3904, 3906, 3908 can have various configurations, in this illustrated embodiment, the four sets of tabs 3902, 3904, 3906, 3908 each have a hook-shaped configuration that engages a respective portion of the opposing outer flanges 3910a, 3910b, 3910a, 3910b, 3914a, 3914b, 3914a, 3914b of the cartridge 3901. Additionally, when the cartridge 3901 includes a longitudinal slot 3918, such as a knife slot, the second outer layer 3900 can include a pin feature 3912 configured to engage the longitudinal slot 3918. For example, the pin feature 3912 can include multiple sets of two opposing pins that are intermittently spaced apart relative to one another along the longitudinal slot 3918 (only one set of two opposing tabs 3912A, 3912B is shown in FIGS. 39A-39B ). FIG. 39B As shown in greater detail in

[0299] As described above, in some embodiments, the second outer layer may be an adhesive film. In one exemplary embodiment, such as... FIG. 40 As shown, accessory 4000 is installed in warehouse 4001 (e.g. FIG. 1 The appendage 4000 is located on the top surface 4001a of the compartment 200 in Figure 2c. The appendage 4000 includes an internal structure 4002, a first outer layer 4004 disposed on the top surface 4002a of the internal structure 4002, and a second outer layer 4006 disposed on the opposite bottom surface 4000b, opposite the top surface 4002a of the internal structure 4002. Except for the differences discussed below, the appendage 4000 may be similar to... FIGS. 37A-38A The appendage 3700 is included, and therefore common features are not described in detail herein. As shown in the figure, the internal structure 4002 consists of interconnected repeating cells 4008 (such as...). FIGS. 8A-9B Cell 810 in the image is formed. Additionally, the second outer layer 4006 is in the form of an adhesive film attached to the top surface 4001a of the chamber 4001. In this illustrated embodiment, the second layer 4006 is an adhesive film formed of a pressure-sensitive adhesive. Further details regarding the adhesive film and other attachment methods can be found in U.S. Patent No. 10,349,939, the entire contents of which are incorporated herein by reference.

[0300] Dimple grid

[0301] In some embodiments, the appendage may further include a grid structure extending from the second outer layer and configured to be inserted into a nail recess or channel in the nail cartridge. For example, as FIG. 41A As shown, the appendage 4100 includes an internal grid structure 4102 extending between two outer layers 4104, 4106. The internal grid structure 4102 is generally formed of interconnected repeating cells, and any repeating cells disclosed herein may be used when the repeating cells are omitted from this illustration. Additionally, each of the two outer layers 4104, 4106 may be formed by a grid structure or as a membrane, and thus, each of the two outer layers is approximately... FIGS. 41A-41C As shown in the diagram. The first outer layer 4106 is configured to contact tissue, and as... FIGS. 41B-41C As shown, the second outer layer 4104 is configured to contact the compartment 4101. The compartment 4101 is similar to... FIGS. 1-2C The warehouse is 200, and therefore the common features are not described in detail in this paper.

[0302] like FIGS. 41A-41CFurther shown, the adjunct 4100 includes staple pocket lattices 4110a, 4110b, 4110c extending outwardly from the second outer layer 4104. The staple pocket lattices can function as separate compression zones of the adjunct 4100, e.g., the staple pocket lattices 4110a, 4110b, 4110c can have a different compression rate than the overall adjunct, so as to substantially not increase the solid height of the overall adjunct. While the staple pocket lattices can have various configurations, in this illustrated embodiment, there are two sets of three longitudinal rows of staple pocket lattices 4110a, 4110b, 4110c on opposite sides of the intended cut line of the adjunct. While the staple pocket lattices can have various configurations, each staple pocket lattice is formed by five U-shaped struts. The shape and size of the perimeter around each staple pocket lattice 4110a, 4110b, 4110c can be triangular or diamond-shaped, and can be complementary to the shape and size of the corresponding staple pockets 4112a, 4112b, 4112c, which can be triangular or diamond-shaped. In other embodiments, the shape and size of the lattice structure and the staple pockets can be different. As FIGS. 41B-41C shown, once the adjunct 4100 is disposed on the cartridge 4101, at least a portion of the staples 4114a, 4114b, 4114c within the cartridge 4101 extend through the corresponding staple pocket lattices 4110a, 4110b, 4110c, and thus are captured by the staple crowns when the adjunct is stapled to tissue. Thus, the staple pocket lattices can also help attach the adjunct to the staple cartridge and / or the alignment of the adjunct relative to the staples.

[0303] The structural configurations of the unit cells disclosed herein can also be tailored to achieve variable mechanical responses in, e.g., lateral and / or longitudinal directions (e.g., y-direction and / or z-direction, respectively) within the same adjunct. For example, in certain embodiments, an adjunct can be formed from at least two or more different lattice structures placed side-by-side, so as to produce at least two substantially different compression characteristics within the same adjunct.

[0304] As FIG. 42AAs generally shown, adjunct 4200 can have one interior lattice structure 4202 and two exterior lattice structures 4204, 4206, with each lattice structure 4202, 4204, 4206 defining a respective compression zone CI, C2, C3 of adjunct 4200. In this embodiment, the first and second exterior lattice structures are structurally identical, and thus C2 and C3 are identical. As shown, the lattice structures 4202, 4204, 4206 are laterally offset from one another relative to the longitudinal axis of adjunct 4200. That is, the first exterior lattice structure 4204 is positioned directly adjacent a first longitudinal side (obscured) of interior lattice structure 4202, and the second exterior lattice structure 4206 is positioned directly adjacent a second, opposite longitudinal side (obscured) of interior lattice structure 4202. Since each lattice structure can be formed from any of the repeating unit cells disclosed herein, the three lattice structures 4202, 4204, 4206 are shown without any unit cells. Those skilled in the art will appreciate that each lattice structure can be formed from either a strut-based repeating unit cell or a non-strut-based repeating unit cell.

[0305] As further shown, a contemplated cut line C L of adjunct 4200 is defined across interior lattice structure 4202 and along the longitudinal axis L A of adjunct 4200. Thus, in this illustrated embodiment, interior lattice structure 4202 can be configured to be stiffer, and thus exhibit a higher resistance to compression, as compared to exterior lattice structures 4204, 4206. Thus, the resulting adjunct 4200 can have a variable compressive strength in the lateral direction (e.g., y-direction) relative to the cut line C L of adjunct 4200. Thus, when the adjunct is sutured to tissue, this variable compressive strength can thus ease the transition of tissue compression at the outermost staple row 4210, as FIG. 42B shown.

[0306] FIGS. 43A-43B Another embodiment of an adjunct 4300 having a variable compressive strength along the lateral direction (e.g., y-direction) relative to its longitudinal axis L A is shown. In this illustrated embodiment, adjunct 4300 is formed from three different lattice structures 4310, 4320, 4330, each formed from a different repeating unit. More specifically, first lattice structure 4310 is formed from first repeating unit cells 4310a interconnected with one another, with one unit cell shown in FIG. 43A , second lattice structure 4320 is formed from second repeating unit cells 4320a interconnected with one another, with one unit cell shown in FIG. 43A , and third lattice structure 4330 is formed from third repeating unit cells 4330a interconnected with one another, with one unit cell shown inFIG. 43A As shown in the figure. As described in more detail below, by designing each grid structure differently, the resulting appendages can have a variety of lateral compression responses.

[0307] While repeating cells 4310a, 4320a, and 4330a can have various configurations, in this illustrated embodiment, repeating cells 4310a, 4320a, and 4330a are cells based on all the struts. Furthermore, depending on the position of the corresponding grid structure, the repeating cells can be structurally configured to be stiffer or less stiff than repeating cells in other grid structures, as described in more detail below.

[0308] Although the three grid structures 4310, 4320, and 4330 can be positioned relative to each other in various different configurations, the first grid structure 4310 is the intended cutting line C of its appendage 4300. L Extending through it and along the longitudinal axis L A The central grid structure of the appendages. Therefore, compared to the second and third repeating cells, the first repeating cell 4310a can have a less compact structural configuration and is therefore more flexible, for example, as... FIG. 43B As shown. Additionally, the first grille structure 4310 extends along the entire length L of the appendage 4300. The second grille structure 4320 is divided into two longitudinal portions 4325a and 4325b. The first longitudinal portion 4325a of the second grille structure 4320 is positioned against the first longitudinal sidewall L1 of the first grille structure 4310, and the second longitudinal portion 4325b of the second grille structure 4320 is positioned against the second opposing longitudinal sidewall L2 of the first grille structure 4310 (see...). FIG. 43A Based on its relationship with the cutting line C. L In terms of position, compared to the first repeating cell 4310a and the third repeating cell 4330a, the second repeating cell 4320a can be constructed to be the most compact and therefore the most rigid, for example, as FIG. 43A As shown.

[0309] like FIG. 43B As further shown, the third grille structure is divided into two U-shaped portions 4335a and 4335b, wherein each U-shaped portion is positioned against the outer wall of the corresponding first longitudinal portion 4325a and second longitudinal portion 4325b of the second grille structure 4320. FIG. 43Aonly the outer longitudinal walls L3 and L4 of each repeating cell 4325a, 4325b are shown). Thus, the third lattice structure 4320 defines at least a portion of the outer perimeter of the adjunct 4300. Based on the location of the third lattice structure 4330, the third repeating unit cell can be configured to impart an intermediate density, and thus an intermediate stiffness, as compared to the first and second repeating unit cells 4310a, 4320a, as FIGS. 44A-44C As shown, this can help to ease the transition of tissue compression. Additionally, the structural configuration of the third repeating unit cell 4330a can be configured to promote tissue growth. In certain embodiments, the third lattice structure can also be disposed onto at least a portion of the top surface of the second lattice structure, which can further enhance tissue ingrowth into the adjunct.

[0310] In some embodiments, the dimensions (e.g., wall thickness and / or height) of the repeating unit cells can vary between other repeating unit cells. For example, FIGS. 44A-44B Another embodiment of an adjunct 4400 having a variable compressive strength along a transverse direction (e.g., y-direction) relative to its longitudinal axis (e.g., z-direction) due to varying dimensions of the strutless repeating unit cells is shown. As shown, FIGS. 44A-44C As shown, only half (e.g., the left half) of the adjunct 4400 is shown on a staple cartridge 4401 having three rows of staples 4405a, 4405b, 4405c. While the three rows of staples 4405a, 4405b, 4405c can be generally uniform (e.g., nominally the same within manufacturing tolerances), in this illustrated embodiment, the staple height of the third row of staples 4405c (e.g., the outermost row of staples) is greater than the staple height of the first and second rows of staples 4405a, 4405b. This difference in staple height can help the overall compression behavior of the adjunct. In this illustrated embodiment, the third row of staples 4405c will exert a compression force on the captured tissue and adjunct within, for example, the staple catch region that is less than the compression force exerted by the first and second rows of staples 4405a, 4405b on the respective captured tissue and adjunct within, for example, the respective staple catch regions. The adjunct 4400 includes two sets of three longitudinal arrays of repeating unit cells. Since both sets are identical, FIGS. 9A-9B Only one set of three arrays 4410, 4412, 4414 and only one repeating unit cell 4410a, 4412a, 4414a of each of the three arrays is shown.

[0311] The repeating unit cells 4410a, 4412a, 4414a can have various configurations. In this illustrated embodiment, the repeating unit cells 4410a, 4412a, 4414a are generally hexagonal in overall shape, with the repeating unit cells 4410a, 4412a, 4414a being generally uniform in size. FIGS. 8A-9BThe repeating cell 810 is similar. However, the wall thickness and height between at least two repeating cells can vary. As shown, the wall thickness W from the innermost repeating cell 4410a (e.g., the first repeating cell) to the outermost repeating cell 4414a (e.g., the third repeating cell) is... T Decrease. That is, decrease the wall thickness W of the innermost repeating cell 4410a. T1 The wall thickness W is greater than the middle repeating cell 4412a. T2 And the wall thickness W of the repeating grid 4412a in the middle. T2 The wall thickness W is greater than the outermost repeating cell 4414. T3 Additionally, although the heights H1 and H2 of each of the innermost repeating cell 4410a and the middle repeating cell 4412a are the same, their heights H1 and H2 are greater than the height H3 of the outermost repeating cell 4414a. In other embodiments, only the wall thickness or height varies between arrays, or the wall thickness varies between only two of the three arrays, or the height varies between all three arrays.

[0312] Alternatively or otherwise, the shape of repeating cells may be consistent with Schwarz-P structures (such as...). FIG. 44A In cases similar to the Schwarz-P structure 810, the length of the hollow tubular interconnects between repeating cells in different arrays can vary. For example, as... FIGS. 44B-44C As further shown, the hollow tubular interconnect 4416 between the innermost repeating cell 4410a and the middle repeating cell 4412a extends with a first length L1, and the hollow tubular interconnect 4418 between the middle repeating cell 4412a and the outermost repeating cell 4414a extends with a second length L2 greater than the first length L1.

[0313] exist Cartridge surface featuresThe compressive behavior of the repeating cells 4410, 4410a of the adjunct 4400 as the adjunct 4400 is sutured to tissue is illustrated schematically in FIG. 44. Thus, the change in size of the repeating cells in the lateral direction results in three different compression zones having different compressive strengths, a first zone defined by a first longitudinal array 4410 of first repeating cells 4410a having a first compressive strength (e.g., the ability of the structure to withstand compressive forces in the x-direction), a second zone defined by a second longitudinal array 4412 of second repeating cells 4412a, and a third zone defined by a third longitudinal array 4414 of third repeating cells 4414a having a third compressive strength. While the compressive strength can vary in each array, in this illustrated embodiment, the first compressive strength is greater than the second compressive strength, and the second compressive strength is greater than the third compressive strength. Thus, the first repeating cells 4410a are stiffer than the second repeating cells 4412a, and the second repeating cells 4412a are stiffer than the third repeating cells 4414a.

[0314] FIGS. 45A-45C

[0315] In some embodiments, the staple cartridge can include surface features (e.g., staple pocket protrusions) that can be configured to interact with the adjunct to help retain the adjunct to the staple cartridge prior to staple deployment. For example, in certain embodiments, the surface features can include protrusions that extend outwardly from the top surface of the staple cartridge. Alternatively, or in addition thereto, the surface features can include recessed channels defined within the top surface of the staple cartridge. Accordingly, the adjuncts described herein can be designed in various configurations that are adapted to interact with the surface features of the staple cartridge, if present, and thus enable a releasable attachment mechanism between the adjunct and the staple cartridge. Alternatively, or in addition thereto, the adjuncts described herein can be designed in various configurations that are adapted to interact with the legs of the staples that extend outwardly from their respective cavities within the staple cartridge.

[0316] FIGS. 45B-45C An exemplary embodiment of a buttressless adjunct 4500 that can be configured to interact with surface features 4504 of a staple cartridge 4502 is illustrated. Alternatively, or in addition thereto, the adjunct 4500 can be configured to interact with the legs of staples 4506, 4507, 4508 disposed at least partially within the staple cartridge 4502 (see FIGS. 1-2C ). While the staple cartridge 4502 can have various configurations, in this illustrated embodiment, the staple cartridge 4502 is similar to the staple cartridge 4500 described above with respect to FIG. 45. Thus, the adjunct 4500 can be configured to interact with the surface features 4504 of the staple cartridge 4502 and / or the legs of the staples 4506, 4507, 4508 disposed at least partially within the staple cartridge 4502. FIGS. 45A-45CThe staple cartridge 200 in FIG. 45 is similar to the staple cartridge 200 in FIG. 44, except that the surface features 4504 are U-shaped protrusions that extend outwardly from the top surface 4502a of the staple cartridge and are positioned around respective end portions of the staple cavities defined within the staple cartridge 4502. As shown, the staple cavities are disposed in first and second sets of three longitudinal rows 4510a, 4510b, 4510c, 4512a, 4512b, 4512c and are positioned on first and second sides of the longitudinal slot 4514, respectively. In addition, for each set, the first and third longitudinal rows 4510a, 4510c, 4512a, 4512c are parallel to each other, while the second longitudinal rows 4510b, 4512b are staggered relative thereto.

[0317] As FIGS. 9A-9B further shown, the adjunct 4500 is formed from interconnected repeating cells 4516, wherein each cell is structurally similar to the repeating cell 810 in FIG. 44. Thus, the adjunct 4500 is similar to the adjunct 800 in FIG. 44, except that the repeating cells 4515 are rotated 45 degrees about the X-axis relative to the repeating cells 810 in FIG. 44. In other words, the adjunct 800 is shown in a 0 to 90 degree configuration, while the adjunct 4500 is shown in a ±45 degree orientation. As such, the repeating cells 4516 are oriented in a manner (e.g., repeating pattern) that can coincide with the location of the surface features 4504 and / or the staple cavities 4510a, 4510b, 4510c, 4512a, 4512b, 4512c. FIGS. 8A-8F FIG. 8A As FIG. 45A further shown, the adjunct 4500 is formed from interconnected repeating cells 4516, wherein each cell is structurally similar to the repeating cell 810 in FIG. 44. Thus, the adjunct 4500 is similar to the adjunct 800 in FIG. 44, except that the repeating cells 4515 are rotated 45 degrees about the X-axis relative to the repeating cells 810 in FIG. 44. In other words, the adjunct 800 is shown in a 0 to 90 degree configuration, while the adjunct 4500 is shown in a ±45 degree orientation. As such, the repeating cells 4516 are oriented in a manner (e.g., repeating pattern) that can coincide with the location of the surface features 4504 and / or the staple cavities 4510a, 4510b, 4510c, 4512a, 4512b, 4512c.

[0318] As FIG. 45A further shown, the adjunct 4500 is formed from interconnected repeating cells 4516, wherein each cell is structurally similar to the repeating cell 810 in FIG. 44. Thus, the adjunct 4500 is similar to the adjunct 800 in FIG. 44, except that the repeating cells 4515 are rotated 45 degrees about the X-axis relative to the repeating cells 810 in FIG. 44. In other words, the adjunct 800 is shown in a 0 to 90 degree configuration, while the adjunct 4500 is shown in a ±45 degree orientation. As such, the repeating cells 4516 are oriented in a manner (e.g., repeating pattern) that can coincide with the location of the surface features 4504 and / or the staple cavities 4510a, 4510b, 4510c, 4512a, 4512b, 4512c. FIGS. 45B-45C Only the gaps 4518a, 4518b, 4518c, 4520a, 4520b, 4520c are shown and ​ Only the gaps 4518a, 4518b, 4518c, 4522a, 4522b, 4524a, 4524b, 4524c are shown. The first three longitudinal rows 4516a, 4516b, 4516c are configured to overlap respective staple cavity rows 4510a, 4510b, 4510c, the middle row 4516d is configured to overlap the longitudinal slot 4514, and the last three longitudinal rows 4516e, 4516f, 4516g are configured to overlap respective staple cavity rows 4512a, 4512b, 4512c. Thus, as FIGS. 45B-45C ​As shown in the middle section, based on the position of the surface feature 4504 relative to the nail cavity, each surface feature 4504 overlaps with and at least partially extends through the corresponding gap. Thus, each gap is configured to receive and engage at least one surface feature, thereby holding the appendage 4500 on the cartridge 4502 prior to nail deployment. In other embodiments, all or some of the gaps may be replaced with a thinner area of ​​material into which at least one surface feature can penetrate.

[0319] In addition, such as FIGS. 45B-45C As shown in the middle section, for each row of nail cavities and the corresponding repeating cells in the row, each nail ( FIG. 45B Only nails 4506, 4507, 4508 and their corresponding nail cavity rows 4510a, 4510b, 4510c are shown extending across the corresponding repeating cells, such that each nail leg overlaps with the corresponding gap positioned on one side of the repeating cell. For example, as FIG. 45B As shown, regarding the repeating cell 4515a and the corresponding pin 4508 in the first cell row 4516a, the first leg 4508a and the second leg 4508b of the pin 4508 overlap with the first gap 4518a and the second gap 4518b, respectively, which are on the opposite side of the repeating cell 4515b in the second cell row 4516b. FIG. 45C As further shown, when the appendage 4500 is positioned on the top surface 4502a of the staple cartridge 4502, the staple legs 4507a and 4507b extend through the gaps 4522a and 4522b, respectively. This further retains the appendage 4500 in the cartridge 4502 before staple deployment. Therefore, repeating cells of the appendage can be configured to be positioned and engaged with the first and second staple legs of the corresponding staple.

[0320] FIGS. 46A-46B Another exemplary embodiment of a strut-based appendage 4600 that can be configured to interact with surface features of the staple cartridge 4602 is shown. The staple cartridge 4602 is similar to... FIG. 39A The staple cartridge 3901 is described in detail herein, and therefore common features are not described in detail. Each surface feature has a U-shaped configuration and is positioned around the corresponding end portion of each staple cavity, and thus extends along the corresponding longitudinal row of staple cavities. FIGS. 46A-46B Only the nail cavities 4603a, 4603b, and 4603c of the three longitudinal rows are shown, and therefore the surface features of the three longitudinal rows are shown.

[0321] like FIG. 46BAs shown in more detail, the first surface features of the longitudinal row (only four first surface features 4604a, 4604b, 4604c, 4604d are shown) and the third surface features of the longitudinal row (only four third surface features 4608a, 4608b, 4608c, 4608d are shown) are laterally aligned with each other in the y-direction, thus forming a set of first transverse rows 4605a, 4605b, 4605c, 4605d, each transverse row having a corresponding first and third surface features. The second surface features of the longitudinal row (only four second surface features 4606a, 4606b, 4606c, 4606d are shown) are laterally offset relative to the first and second surface features in the z-direction, thus forming a set of second transverse rows 4607a, 4607b, 4607c, 4607d, each transverse row having a corresponding second surface feature.

[0322] In addition, apart from the differences described in detail below, accessory 4600 is similar to FIGS. 30A-30B The appendage 3000. The appendage 4600 includes a tissue contact layer 4616, a compartment contact layer 4618, and an internal structure 4620 extending therebetween.

[0323] like FIG. 46A As shown, and in FIG. 46B As shown in more detail, each opening within the cartridge contact layer 4618 (only eight openings 4622a, 4622b, 4622c, 4622d, 4622e, 4622f, 4622g, 4622h are shown) is configured to receive at least one corresponding surface feature. Therefore, when the appendage 4600 is positioned on the cartridge 4602, the corresponding surface feature extends into and engages with the corresponding opening within the cartridge contact layer 4618. For example, as... FIG. 46B As shown, the first surface feature portion 4604a and the third surface feature portion 4608a of the first transverse row 4605a extend into the first opening 4622a and engage with at least the first cross brace 4624a, while the second surface feature portion 4606a of the second transverse row 4607a extends into the second opening 4622b and engages with at least the first cross brace 4624a and the opposite cross brace 4624b.

[0324] Cross bracing of the 4618 contact layer of the warehouse ( FIG. 46BOnly eight of the cross struts 4624a, 4624b, 4624c, 4624d, 4624e, 4624f, 4624g) are shown in this example, but the tissue contact layer 4618 can have various configurations. For example, in some embodiments, the width (e.g., in the z-direction) of the cross struts can be generally uniform (e.g., uniform within manufacturing tolerances), while in other embodiments, the width of the cross struts can be non-uniform. In this illustrated embodiment, the width of the cross struts 4624a, 4624c, 4624e, 4624g is uniform, while the width of the remaining cross struts 4624b, 4624d, 4624f is non-uniform. Those skilled in the art will appreciate that the structural configuration of the cross struts of the tissue contact layer can depend at least on the structural configuration of the surface feature. For example, in this illustrated embodiment, at least a portion of the cross struts include curved segments to accommodate the U-shaped configuration of the surface feature. Depending on the orientation of the U-shaped configuration, some of the curved segments have a convex configuration, while others have a concave configuration. Additionally, while the tissue contact layer 4616 of the cross struts 4626a, 4626b, 4626c, 4626d, 4626e, 4626f, 4626g can have various configurations, as shown below, the cross struts 4626a, 4626b, 4626c, 4626d, 4626e, 4626f, 4626g are structurally similar to the corresponding cross struts 4624a, 4624b, 4624c, 4624d, 4624e, 4624f, 4624g of the cartridge contact layer 4618. FIG. 46A

[0325] Variable tissue gap

[0326] ​In some embodiments, it can be desirable to have a variable tissue gap between the adjunct and the anvil to enhance the gripping and stabilization of the tissue during stapling and / or cutting of the tissue. However, a variable tissue gap can adversely affect the ability of the adjunct to apply a generally uniform pressure to the stapled tissue. Accordingly, and as described in greater detail below, the adjuncts disclosed herein can be configured to create a variable tissue gap for tissue manipulation and, when stapled to the tissue, the adjuncts can further be configured to apply a generally uniform pressure (e.g., a pressure in a range of about 30 kPa to 90 kPa) to the tissue stapled thereto for a predetermined period of time (e.g., at least 3 days). In certain embodiments, the adjuncts can apply a pressure of at least about 30 kPa for at least three days. In such embodiments, after 3 days, the adjuncts can be configured to apply an effective amount of pressure (e.g., about 30 kPa or less) to the tissue such that the tissue can remain sealed through the healing period of the tissue (e.g., about 28 days). For example, the adjuncts can be configured to apply a pressure to the stapled tissue that decreases (e.g., linearly decreases) from about 30 kPa to 0 kPa over a predetermined period of time of about 3 days to 28 days, respectively.

[0327] Generally, the adjuncts can include a tissue-contacting surface, a cartridge-contacting surface, and an internal structure extending therebetween, wherein the internal structure includes at least two lattice structures each having a different compressive strength. The at least two lattice structures can vary laterally along a width thereof and / or longitudinally along a length thereof in structure, shape, or interconnection to form a variable tissue gap. In some embodiments, a base geometry of the adjunct can be formed by strutless cells. In such embodiments, an outer geometry of the adjunct can be formed by strut-based lattice structures. In other embodiments, the base geometry can be formed by strut-based cells.

[0328] FIGS. 47A-47B An exemplary embodiment of a surgical end effector 4700 is shown having an anvil 4702 and a stapling assembly 4704. The stapling assembly 4704 includes an adjunct 4706 releasably held on a top surface or deck surface 4707a (e.g., anvil-facing staple cartridge surface) of a staple cartridge 4707. The staple cartridge 4707 is similar to the cartridge 200 in FIGS. 1-2C and thus common features are not described in detail herein. Although not shown, the anvil 4702 is pivotally coupled to an elongate channel, like the elongate channel 104 in FIG. 1 and the stapling assembly 4704 is positioned within and coupled to the elongate channel. Although the anvil 4702 can have a variety of configurations, like the anvil 102 in FIGS. 47A-47BAs shown, however, the anvil includes a surface facing the chamber, which has nail recesses 4708 defined therein, wherein a generally planar tissue-compression surface 4710 (e.g., flat within manufacturing tolerances) extends between the nail recesses 4708 (e.g., extending in the y direction). FIG. 47A The surgical end effector 4700 is shown in a fully closed position, and therefore the anvil 4702 is also shown. FIG. 47B Tissue T is shown clamped between anvil 4702 and suture assembly 4704 and sutured to appendage 4706 via staples (only two sets of three staples 4712a, 4712b, 4712c, 4714a, 4714b, 4714c are shown). Prior to deployment, in some embodiments, such as FIG. 47A and 47C As shown, the nails may be completely disposed within the nail magazine 4707, while in other embodiments, some or all of the nails may be partially disposed within the nail magazine 4707. Although nails 4712a, 4712b, 4712c, 4714a, 4714b, and 4714c may have various configurations, in this illustrated embodiment, nails 4712a, 4712b, 4712c, 4714a, 4714b, and 4714c have at least a substantially uniform pre-expanded (e.g., unformed) nail height (e.g., nominally identical within manufacturing tolerances). In some embodiments, nails 4712a, 4712b, 4712c, 4714a, 4714b, and 4714c may be substantially uniform (e.g., nominally identical within manufacturing tolerances).

[0329] like FIG. 47A As shown, and in FIG. 47C More specifically, the appendage 4706 has a tissue contact surface 4716, a compartment contact surface 4718, and an internal structure 4720 extending therebetween. While the internal structure 4720 can have various configurations, in this illustrated embodiment, the internal structure includes two grid structures 4722 and 4724, each with a different compressive strength, such that the appendage 4706, when in a tissue deployment state, is configured to apply substantially uniform pressure to the sutured tissue for a predetermined period of time. In this illustrated embodiment, the first grid structure 4722 is configured to have a first compressive strength, and the second grid structure 4724 is configured to have a second compressive strength greater than the first compressive strength.

[0330] Each of the first lattice structure 4722 and the second lattice structure 4724 can generally be formed of cells, such as those disclosed herein, e.g., struts-based cells and / or non-strut-based cells. For example, in certain embodiments, one or more of the cells can include at least one triply periodic minimal surface structure, such as those disclosed herein. Alternatively or additionally, one or more of the cells can be defined by interconnected struts, e.g., planar struts, such as strut-based cells disclosed herein. In certain embodiments, the first lattice structure 4722 and the second lattice structure 4724 can vary in density (e.g., number of cells) and / or shape. Accordingly, particular structural configurations of each of the first lattice structure 4722 and the second lattice structure 4724 are not shown, in addition to the general shape and thickness.

[0331] The first lattice structure 4722 and the second lattice structure 4724 each extend from a top surface 4722a, 4724a to a bottom surface 4722b, 4724b. Depending on the overall structural configuration of the adjunct, at least a portion of the top surface of at least one of the lattice structures can function as a tissue-contacting surface of the adjunct, and at least a portion of the bottom surface of at least one of the lattice structures can function as a cartridge-contacting surface of the adjunct. In the illustrated embodiment, the first lattice structure 4722 is positioned on top of the second lattice structure 4724 such that the bottom surface 4722b of the first lattice structure 4722 and the top surface 4724a of the second lattice structure 4724 are in contact. Accordingly, the top surface 4722a of the first lattice structure 4722 thus forms the tissue-contacting surface 4716, and the bottom surface 4724b of the second lattice structure 4724 thus forms the cartridge-contacting surface 4718. Accordingly, the shape of the top surface 4722a of the first lattice structure 4722 can create a tissue gap between the anvil 4702 and the stapling assembly 4704 that is independent of the shape of the top surface or deck surface 4707a of the staple cartridge 4707.

[0332] The top and bottom surfaces 4722a, 4724a, 4724a, 4724b of each lattice structure 4722, 4724 can have a variety of different shapes. In the illustrated embodiment, the top and bottom surfaces 4722a, 4722b of the first lattice structure 4722 each have a convex configuration. As a result, the top surface 4724a of the second lattice structure 4724 has a concave configuration. Additionally, since the top or deck surface 4707a of the staple cartridge 4707 has a generally planar configuration (e.g., in the YZ plane), the bottom surface 4724b of the second lattice structure 4724 also has a generally planar configuration (e.g., in the YZ plane). As a result, the resulting overall geometry of the adjunct 4706 creates a curved tissue contact surface 4716 relative to the tissue-compression surface 4710 of the anvil 4702 and, thus, a variable tissue gap (e.g., two different amounts of gap are shown as T G1 , T G2 ).

[0333] In the illustrated embodiment, due to the concave shape of the top surface 4722a of the first lattice structure 4722, the overall thickness T C (e.g., in the x-direction) of the adjunct 4706 at its center (represented by the dashed line 4726, e.g., equidistant from the two opposing terminal transversely-facing edges 4728a, 4728b, etc.) is greater than the overall thickness T P1 , T P2 (e.g., in the x-direction) at each of the terminal transversely-facing edges 4728a, 4728b of the adjunct 4706 (e.g., the outer longitudinal perimeter of the adjunct 4706 extending in the z-direction). As a result, the overall uncompressed thickness of the adjunct 4706 varies laterally outward (e.g., ±y-direction) relative to its center along its width and, thus, laterally relative to the longitudinal axis of the adjunct 4706 (e.g., extending in the z-direction). As a result, the uncompressed thickness of the adjunct decreases in the lateral direction as the tissue gap increases. Additionally, since the two terminal transversely-facing edges 4728a, 4728b are shown as having the same thickness, the change in lateral thickness from the center of the adjunct 4706 to each edge is the same. In other embodiments, the two terminal transversely-facing edges can have different thicknesses and, thus, the change in lateral thickness from the center of the adjunct to the respective edge would be different.

[0334] As further shown, due to the concave-convex surface relationship between the first lattice structure 4722 and the second lattice structure 4724 and their position and compression strength relative to one another, the thickness (e.g., in the x-direction) of each lattice structure also varies laterally outward (e.g., ±y-direction) along its respective length relative to its respective center, which in this embodiment is also the center of the adjunct 4706 (indicated by dashed line 4726). Thus, in this illustrated embodiment, the first lattice structure 4722 is thicker than the second lattice structure 4724 at the center of the adjunct, and the second lattice structure 4724 is thicker than the first lattice structure 4722 at each of the laterally-facing ends 4728a, 4728b of the adjunct 4706. Thus, the adjunct 4706 is most compressible at its center and least compressible at its laterally-facing ends 4728a, 4728B, and thus when in a tissue deployment state, the adjunct 4706 is compressible to a substantially uniform thickness T 压缩 (see FIG. 47B ). This allows the adjunct 4706 to exert a pressure that is not proportional to its uncompressed variable thickness. Thus, when the adjunct is stapled to a substantially uniform tissue T (e.g., tissue having the same or substantially the same thickness across the width of the adjunct in the y-direction) with staples 4712a, 4712B, 4712c, 4714a, 4714B, 4714c, the adjunct 4706 can exert a substantially uniform pressure P (see FIG. 47B ) to the stapled tissue T.

[0335] FIGS. 48A-48B Another example embodiment of a surgical end effector 4800 is shown having an anvil 4802 and a stapling assembly 4804. The stapling assembly 4804 includes an adjunct 4806 releasably held on a top or deck surface 4807a (e.g., anvil-facing staple cartridge surface) of a staple cartridge 4807. The anvil 4802 is similar to the anvil 4702 in FIGS. 47A-47B , and the staple cartridge 4807 is similar to the cartridge 200 in FIGS. 1-2C , except that the top or deck surface 4807a is curved, and thus the common features are not described in detail herein. FIG. 48A The surgical end effector 4800 is shown in a fully closed position, and thus the anvil 4802 is shown, while FIG. 48B the tissue T is shown clamped between the anvil 4802 and the stapling assembly 4802 and stapled to the adjunct 4806 via the staples (only two sets of three staples 4812a, 4812b, 4812c, 4814a, 4814b, 4814c are shown). Prior to deployment, in some embodiments, as in FIG. 48A and 48CAs shown, the nails can be completely disposed within the nail magazine 4807, while in other embodiments, some or all of the nails can be partially disposed within the nail magazine 4807. Although the two sets of nails 4812a, 4812b, 4812c, 4814a, 4814b, 4814c can have various configurations, in this illustrated embodiment, the two sets of nails are identical, and therefore for each set, the first nails 4812a, 4814a (e.g., the nails in the innermost row) have a first height, the second nails 4812b, 4814b (e.g., the nails in the middle row) have a second height greater than the first height, and the third nails 4812c, 4814c (e.g., the nails in the outermost row) have a third height greater than the second height.

[0336] like FIG. 48A As shown, and in FIG. 48C More specifically, the appendage 4806 has a tissue contact surface 4816, a compartment contact surface 4818, and an internal structure 4820 extending therebetween. While the internal structure 4820 can have various configurations, in this illustrated embodiment, the internal structure 4820 includes two grid structures 4822 and 4824, each grid structure having a different compressive strength, such that the appendage 4806, when in a tissue deployment state, is configured to apply substantially uniform pressure to the sutured tissue for a predetermined period of time. In this illustrated embodiment, the first grid structure 4822 is configured to have a first compressive strength, and the second grid structure 4824 is configured to have a second compressive strength greater than the first compressive strength.

[0337] Each of the first grid structure 4822 and the second grid structure 4824 may generally be formed of cells, such as those disclosed herein, such as strut-free cells and / or strut-based cells. For example, in some embodiments, one or more cells may include at least one triple-periodic minimal surface structure, such as those disclosed herein. Alternatively or otherwise, one or more cells may be defined by interconnecting struts (e.g., planar struts), such as strut-based cells disclosed herein. Therefore, apart from general shape and thickness, specific structural configurations of each of the first grid structure 4822 and the second grid structure 4824 are not shown.

[0338] The first lattice structure 4822 and the second lattice structure 4824 each extend from a top surface 4822a, 4824a to a bottom surface 4822b, 4824b. Depending on the overall structural configuration of the adjunct, at least a portion of the top surface of at least one lattice structure can function as a tissue-contacting surface of the adjunct, and at least a portion of the bottom surface of at least one lattice structure can function as a cartridge-contacting surface of the adjunct. In this illustrated embodiment, the first lattice structure 4822 is narrower (e.g., in the y-direction) compared to the second lattice structure and thus is positioned only on top of the central region 4823 of the second lattice structure 4824. As a result, the entire bottom surface 4822b of the first lattice structure 4822 only contacts a portion of the top surface 4824a of the second lattice structure 4824, e.g., only the top surface 4823a of the central region 4823. As a result, the two exposed portions 4825a, 4825b of the top surface 4822a of the first lattice structure 4822 and the top surface 4824a of the second lattice structure 4824 form the tissue-contacting surface 4816, and the bottom surface 4824b of the second lattice structure 4824 forms the cartridge-contacting surface 4818.

[0339] The top and bottom surfaces 4822a, 4824a, 4824a, 4824b of each lattice structure 4822, 4824 can have a variety of different shapes. Those skilled in the art will appreciate that the shape of the top and bottom surfaces can depend at least on the top surface or deck surface of the cartridge on which the adjunct will be releasably held. In this illustrated embodiment, the top and bottom surfaces 4822a, 4822b of the first lattice structure 4822 each have a convex configuration. As a result, the top surface 4823a of the central region 4823 of the second lattice structure 4824 has a convex configuration, while the two exposed portions 4825a, 4825b of the top surface 4824a of the second lattice structure 4824 each have a generally planar configuration (e.g., extend in the y-direction). Additionally, since the top surface or deck surface 4807a of the cartridge 4807 has a convex configuration, the bottom surface 4824b of the second lattice structure 4824 has a concave configuration.

[0340] In this illustrated embodiment, due to the structural interconnection between the first lattice structure 4822 and the second lattice structure 4824 and the resulting shape of the tissue-contacting surface 4816, the overall thickness T C of the adjunct 4806 at the center (represented by the dashed line 4826, e.g., equidistant from the outermost distal laterally-facing edges 4828a, 4828b, etc.) is less than the overall thickness T P1 of the adjunct 4806 at the outer longitudinal periphery of the adjunct 4806 (e.g., extending in the z-direction) at the outermost distal laterally-facing edges 4828a, 4828b (e.g., in the x-direction). P2(For example, in the x direction). Therefore, the total uncompressed thickness of the appendage 4806 varies laterally outward relative to its center along its width (e.g., in the ±y direction). Therefore, the total uncompressed thickness of the appendage varies laterally relative to the longitudinal axis of the appendage 4806 (e.g., extending in the z direction).

[0341] As further illustrated, due to the structural relationship between the first grid structure 4822 and the second grid structure 4824, and the combination of their compressive strength relative to each other and the bending configuration of the top surface 4807a of the staple cartridge 4807, the thickness of each grid (e.g., in the x-direction) also varies laterally outward along its respective length relative to its corresponding center (e.g., in the ±y-direction), which in this embodiment is also the center of the appendage 4806 (indicated by dashed line 4826). Therefore, in this illustrated embodiment, the first grid structure 4822 is thicker than the second grid structure 4824 at the center of the appendage 4806. Consequently, the appendage 4806 is most compressible at its center and least compressible at its outermost, laterally facing edges 4828a, 4828b. This allows the appendage 4806 to be subjected to substantially uniform pressure regardless of variations in its compressive thickness. Therefore, when the appendage is sutured to a substantially uniform tissue T (e.g., tissue with the same or substantially the same thickness across the width of the appendage in the y direction, e.g., in the x direction) using staples 4812a, 4812B, 4812c, 4814a, 4814B, 4814c), the appendage 4806 is compressed to a non-uniform compression thickness while still applying a substantially uniform pressure P to the sutured tissue T (see...). FIG. 48B As further shown, in this illustrated embodiment, only the second grille 4824 overlaps with the outermost nails 4812c and 4814c.

[0342] In other embodiments, the width of the second grid structure may be narrower than the width of the first grid structure. For example, as... FIG. 49 As shown, the appendage 4900 includes a first grid structure 4906 and a second grid structure 4908 having a semi-circular concentric configuration, wherein the first grid structure 4906 surrounds the second grid structure 4908. Therefore, the top surface 4906a of the first grid structure 4906 forms the tissue contact surface 4902 of the appendage 4900, and the bottom surfaces 4906b and 4908b of the first grid structure 4906 and the second grid structure 4908 form the compartment contact surface 4904 of the appendage 4900.

[0343] As described above, the appendage may have two grid structures that vary longitudinally (e.g., in the z-direction) in terms of structure, shape, or interconnection along the length of the appendage. For example, as FIGS. 50A-50BAs shown, the adjunct 5002 includes two lattice structures 5004, 5006, each lattice structure being opposite to each other and along a length of the adjunct (e.g., along a longitudinal axis L A vary in structure and shape.

[0344] FIGS. 50A-50B An exemplary embodiment of a surgical end effector 5000 is shown, which is similar to surgical end effector 5000 except that the adjunct 5002 has a variable compressive strength along its length, which length extends along a longitudinal axis L A (e.g., in the z-direction). As FIG. 50A shown, and as shown in greater detail in FIG. 50C the adjunct 5002 is positioned on a top or deck surface 5003a of a staple cartridge 5003. The staple cartridge 5003 is similar to the staple cartridge 4707 in FIGS. 47A-47C wherein the staples 4712a, 4712b, 4712c, 4714a, 4714b, 4714c are disposed therein, and thus common features are not described herein.

[0345] The adjunct 5002 has a tissue-contacting surface 5008, a cartridge-contacting surface 5010, and an interior structure 5012 extending therebetween. While the interior structure 5012 can have various configurations, the first lattice structure 5004 and the second lattice structure 5006 each have different compressive strengths such that the adjunct 5002 is configured to apply a generally uniform pressure (e.g., a pressure in the range of 30 kPa to 90 kPa) to tissue stapled thereto for a predetermined period of time (e.g., at least 3 days) when in a tissue-deployed state. In this illustrated embodiment, the first lattice structure 5004 is configured to have a first compressive strength, and the second lattice structure 5006 is configured to have a second compressive strength that is greater than the first compressive strength. Thus, the second lattice structure 5004 is stiffer than the first lattice structure 5006. In other embodiments, the first lattice structure can be stiffer than the second lattice structure.

[0346] Each of the first lattice structure 5004 and the second lattice structure 5006 can generally be formed of cells, such as those disclosed herein, e.g., struts-based cells and / or struts-based cells. For example, in certain embodiments, one or more cells can include at least one triply periodic minimal surface structure, such as those disclosed herein. Alternatively or additionally, one or more cells can be defined by interconnected struts (e.g., planar struts), such as struts-based cells disclosed herein. In certain embodiments, the first lattice structure 5004 and the second lattice structure 5006 can vary in density (e.g., number of cells) and / or shape. Thus, particular structural configurations of each of the first lattice structure 5004 and the second lattice structure 5006 are not shown, in addition to the general shape and thickness.

[0347] The first lattice structure 5004 and the second lattice structure 5006 each extend from a top surface 5004a, 5006a to a bottom surface 5004b, 5006b. Depending on the overall structural configuration of the adjunct, at least a portion of the top surface of at least one lattice structure can function as a tissue-contacting surface of the adjunct, and at least a portion of the bottom surface of at least one lattice structure can function as a cartridge-contacting surface of the adjunct. In this illustrated embodiment, the first lattice structure 5004 is positioned on top of the second lattice structure 5006 such that the bottom surface 5004b of the first lattice structure 5004 and the top surface 5006a of the second lattice structure 5006 are in contact. Thus, the top surface 5004a of the first lattice structure 5004 forms a tissue-contacting surface 5008, and the bottom surface 5006b of the second lattice structure 5006 forms a cartridge-contacting surface 5010.

[0348] While the first lattice structure 5004 and the second lattice structure 5006 can have various configurations, each lattice structure has a varying uncompressed thickness (e.g., in the x-direction) along the length of the adjunct (e.g., extending in the z-direction). As shown, the top surface 5004a of the first lattice structure 5004 is sloped from the proximal end 5002a to the distal end 5002b of the adjunct 5002. Additionally, since the top surface or deck surface 5003a of the staple cartridge 5003 has a generally planar configuration (e.g., in the XZ plane), the bottom surface 5006b of the second lattice structure 5006 also has a generally planar configuration (e.g., in the XZ plane). Thus, a variable tissue gap (e.g., two different amounts of gap are shown as T G1 、T G2 ) is created between the anvil 5001 and the adjunct 5002, which is independent of the shape of the top surface or deck surface 5003a of the staple cartridge 5003.

[0349] When the adjunct is stapled to tissue, asFIG. 50B As shown, the uncompressed thickness of each lattice structure varies along the apposition length in combination with the first and second compression strengths and the variable tissue gap can allow the apposition to apply a substantially uniform pressure P to the stapled tissue T (see FIG. 50B ).

[0350] Consistent tissue gap

[0351] In some embodiments, it can be desirable to have a uniform tissue gap between the apposition and the anvil to enhance tissue grasping and stability during stapling and / or cutting of tissue. However, a uniform tissue gap can adversely affect the ability of the apposition to apply a substantially uniform pressure to the stapled tissue. Accordingly, and as described in greater detail below, the appositions disclosed herein can be configured to create a uniform tissue gap for tissue manipulation and, when stapled to tissue, the appositions can be further configured to apply a substantially uniform pressure (e.g., a pressure in the range of about 30 kPa to 90 kPa) to the tissue stapled thereto for a predetermined period of time (e.g., at least 3 days). In certain embodiments, the appositions can apply a pressure of at least about 30 kPa for at least three days. In such embodiments, after 3 days, the appositions can be configured to apply an effective amount of pressure (e.g., a pressure that linearly decreases, such as about 30 kPa or less) to the tissue such that the tissue can remain sealed through the healing period of the tissue (e.g., about 28 days). For example, the appositions can be configured to apply a pressure to the stapled tissue, where the pressure decreases (e.g., linearly decreases) from about 30 kPa to 0 kPa over a predetermined period of time of about 3 days to 28 days, respectively.

[0352] In some embodiments, the appositions can be designed with a tissue-contacting surface that is substantially planar (e.g., in the y-direction) for at least a portion thereof and a non-planar opposing cartridge-contacting surface (e.g., along the width of the apposition, such as in the y-direction). The non-planar surface of the cartridge-contacting surface can vary proportionally along and relative to a curved or stepped top or deck surface of the cartridge (e.g., the cartridge surface facing the anvil) or a stepped tissue-compression surface of the anvil, for example.

[0353] Generally, the adjunct can include a tissue-contacting surface, a cartridge-contacting surface, and an internal structure extending therebetween. In some embodiments, the adjunct can be formed from at least two lattice structures, wherein a first lattice structure has a non-planar bottom surface defining at least a portion of the cartridge-contacting surface; and a second lattice structure (e.g., a primary lattice structure) has a top surface with at least a portion that is generally planar and defines at least a portion of the tissue-contacting surface. In other embodiments, the internal structure can be formed from a single lattice structure formed from repeating cells that vary in shape and / or size in a transverse direction relative to a longitudinal axis of the adjunct. Thus, the adjunct can have an overall geometry that creates a tissue-contacting surface having planar and non-planar surfaces and a non-planar cartridge-contacting surface (e.g., anvil-facing cartridge surface) configured to mate to a curved or stepped top or deck surface of a staple cartridge. Thus, a generally uniform tissue gap can be created independent of the shape of the top or deck surface of the staple cartridge.

[0354] In some embodiments, the dimensions (e.g., wall thickness and / or height) of the repeating cells can vary such that when the adjunct is stapled to tissue, the adjunct can apply a generally uniform pressure (e.g., a pressure in the range of 30 kPa to 90 kPa) to the stapled tissue for a predetermined period of time (e.g., at least three days). For example, one longitudinal row of repeating cells can vary relative to an adjacent longitudinal row of repeating cells. Thus, the adjunct can be designed in such a way that it can create a tissue gap that conforms to the anvil prior to staple deployment and, when in a tissue-deployed state, can apply a generally uniform pressure (e.g., a pressure in the range of 30 kPa to 90 kPa) to the stapled tissue for a predetermined period of time (e.g., at least three days).

[0355] FIG. 51A An exemplary embodiment of a surgical end effector 5100 is shown having an anvil 5102 and a stapling assembly 5104. The stapling assembly 5104 includes an adjunct 5106 releasably retained on a top or deck surface 5108a (e.g., anvil-facing cartridge surface) of a staple cartridge 5108. The staple cartridge 5108 is similar to the cartridge 4807 in FIGS. 48A-48C except for the differences described below, and thus common features are not described in detail herein. Although not shown, the anvil 5102 is pivotally coupled to an elongate staple channel, such as the elongate staple channel 104 in FIG. 1 except for the differences described below, and thus common features are not described in detail herein. Although not shown, the anvil 5102 is pivotally coupled to an elongate staple channel, such as the elongate staple channel 104 in FIG. 51AIn the illustrated embodiment, the anvil 5102 includes a surface facing the chamber having staple recesses 5110 defined therein, wherein a generally planar tissue-compression surface 5112 extends between the staple recesses 5110. FIG. 51A A surgical end effector 5100 in a fully closed position is shown, and thus an anvil 5102 is shown, wherein tissue is not positioned between the anvil 5102 and the appendage 5106 and the staples are not disposed within the staple cartridge 5108 (only two sets of three staples 5114a, 5114b, 5114c, 5116a, 5116b, and 5116c are shown). Prior to deployment, in some embodiments, such as FIG. 51A As shown, nails 5114a, 5114b, 5114c, 5116a, 5116b, and 5116c may be partially disposed within nail magazine 5108, while in other embodiments, some or all of the nails may be completely disposed within nail magazine 5108. Although nails 5114a, 5114a, 5114c, 5116a, 5116b, and 5116c may have various configurations, in this illustrated embodiment, nails 5114a, 5114a, 5114c, 5116a, 5116b, and 5116c have at least a substantially uniform pre-expanded (e.g., unformed) nail height (e.g., nominally identical within manufacturing tolerances). In some embodiments, nails 5114a, 5114a, 5114c, 5116a, 5116b, and 5116c may be substantially uniform (e.g., nominally identical within manufacturing tolerances).

[0356] like FIG. 51A As shown, and in FIG. 51B More specifically, the appendage 5106 has a tissue contact surface 5118, a compartment contact surface 5120, and an internal structure 5122 extending therebetween. While the internal structure 5122 can have various configurations, in this illustrated embodiment, the internal structure 5122 includes two distinct grid structures 5124, 5126. The first grid structure 5124 and the second grid structure 5126 each extend from the top surfaces 5124a, 5126a to the bottom surfaces 5124b, 5126b.

[0357] The first grille structure 5124 can typically be composed of, for example FIGS. 52A-52B The struts 5228a, 5228b, 5228c, 5228d, 5230a, 5230b, 5230c, 5230d, or cells such as those disclosed herein (e.g., based on cells without struts and / or cells based on struts) are formed. Therefore, apart from the general overall shape and thickness, the specific structural configuration of the first grid structure 5124 is not shown.

[0358] The first lattice structure 5124 extends between the second lattice 5126 structure and the top or deck surface 5108a of the cartridge 5108. As illustrated, the uncompressed thickness of the first lattice structure 5124 varies laterally with respect to the longitudinal axis L of the longitudinal leg 5106 A (e.g., L A ) extends in the z-direction) varies laterally. These lateral variations can be scaled along the curved top or deck surface 5108a of the cartridge 5108 such that a portion of the cartridge-contacting surface 5120 of the leg 5106 formed by the bottom surface 5124b of the first lattice structure 5124 is complementary in shape to the curved top or deck surface 5108a (e.g., concave configuration) of the cartridge 5108. Thus, the thickness variations of the first lattice structure 5124 can conform to the variations of the top or deck surface 5108a. Additionally, this results in the compression ratio of the first lattice structure 5124 also varying in the lateral direction, which in this illustrated embodiment, increases due to the lateral increase in uncompressed thickness such that the compression behavior of the leg 5106 is primarily driven by the compression characteristics of the second lattice structure 5126.

[0359] The second lattice structure 5126 is formed from interconnected repeating cells arranged in two groups of three longitudinal arrays, with the first group positioned on one side of the intended cut line of the leg and the second group positioned on the second side of the intended cut line of the leg. For simplicity, only three cells from each group 5132a, 5132b, 5132c, 5134a, 5134b, 5134c are illustrated. While the repeating cells can have various configurations, in this illustrated embodiment, all of the repeating cells have generally uniform dimensions (e.g., nominally the same within manufacturing tolerances) and are similar to the repeating cells 810 in FIGS. 9A-9B , and thus the common features are not described in detail herein. Thus, the second lattice structure is similar to the leg 800 in FIGS. 8A-8F , and thus the common features are not described herein.

[0360] As shown, at least a portion of the top surface 5126a is generally planar, and thus includes generally planar surfaces 5127 (e.g., each surface in the y-direction) with non-planar surfaces 5129 extending therebetween. The top surface 5126a defines the tissue contact surface 5118 of the adjunct 5106, and thus the tissue contact surface 5118 is formed from the planar surfaces 5127 and the non-planar surfaces 5129. As the generally planar surfaces 5127 and the non-planar surfaces 5129 of the top surface (and thus the tissue contact surface 5118) alternate along the width of the second lattice structure 5126 (extending in the y-direction), a consistent tissue gap (e.g., alternating between generally uniform tissue gaps and variable tissue gaps) is created between the anvil 5102 and the adjunct 5106. In this illustrated embodiment, each generally uniform tissue gap T G occurs between the tissue-compression surface 5112 of the anvil 5102 and the generally planar surfaces 5127 of the tissue contact surface 5118. Variable tissue gaps (only two variable gaps are shown as T G1 , T G2 ) occur between the tissue-compression surface 5112 of the anvil 5102 and the non-planar surfaces 5129 of the tissue contact surface 5118, which extend between adjacent cells of the second lattice structure 5126. Those skilled in the art will appreciate that the length (extending in the x-direction) of the generally uniform and variable tissue gaps can depend at least on the structural configuration of the tissue contact surface, and thus the structural configuration of the second lattice structure.

[0361] While the height between the repeating cells 5132a, 5132b, 5132c, 5134a, 5134b, 5134c is generally uniform, the wall thickness can vary, and thus result in different compression ratios. In this illustrated embodiment, the two sets of three longitudinal arrays are identical, and thus for each set, the wall thickness W T decreases similarly from the first repeating cell 5132a, 5134a (e.g., the innermost repeating cell) to the third repeating cell 5132c, 5134c (e.g., the outermost repeating cell). Thus, FIG. 51B only one set of three longitudinal arrays is shown. The wall thickness W T1 of the first repeating cell 5132a (not shown) is greater than the wall thickness W T2 of the second repeating cell 5132b (e.g., the middle repeating cell), and the wall thickness W T2 of the second repeating cell 5132b is greater than the wall thickness W T3. Thus, the compression ratio increases from the first repeating cell 5132a, 5134a to the third repeating cell 5132c, 5134c, and thus the first repeating cell 5132a, 5134a will compress the least (e.g., be the hardest) and the third repeating cell 5132c, 5134c will compress the most (e.g., be the least hard). That is, the first compression ratio of the first repeating cell 5132a, 5134a is less than each of the second and third compression ratios of the second and third repeating cells 5132b, 5134b, 5132c, 5134c, and the second compression ratio is less than the third compression ratio. Thus, the combination of these compression ratios with the laterally varying compression ratios of the first lattice structure 5124 will result in a varying overall compression ratio of the adjunct 5106 such that when the adjunct is stapled to tissue using substantially uniform staples 5114a, 5114b, 5114c, 5116a, 5116b, 5116c (e.g., nominally identical within manufacturing tolerances), the adjunct 5106 is configured to apply a substantially uniform pressure to the stapled tissue for a predetermined period of time.

[0362] In certain embodiments, the first lattice structure can be configured in such a way that it does not overlap with the rows of staples when the adjunct is releasably held on the staple cartridge. Thus, the first lattice structure will not be captured by the staples or will be captured to the least extent during deployment. Thus, the first lattice structure will not contribute or will contribute to the least extent to the solid height of the adjunct when in the tissue deployment state. Thus, the densification of the adjunct can be delayed.

[0363] FIG. 52A Another example embodiment of a surgical end effector 5200 is shown having an anvil 5202 and a stapling assembly 5204. The stapling assembly 5204 includes an adjunct 5206 releasably held on a top surface or deck surface 5208a (e.g., anvil-facing staple cartridge surface) of a staple cartridge 5208. The anvil 5202 and the staple cartridge 5208 are similar to the anvil 5102 and the staple cartridge 5208 in FIGS. 52A-52B , except for the differences described below, and thus the common features are not described in detail herein.

[0364] The adjunct 5204 is similar to the adjunct 5104 in FIGS. 51A-51B , except that the first lattice structure 5224 is formed from two sets of four longitudinal rows of spaced-apart vertical planar struts (e.g., in the x-direction) that extend between the second lattice structure 5226 and the top surface or deck surface 5208a of the staple cartridge 5208. As shown, a first set is positioned on one side of the intended cut line C L of the adjunct 5206, and a second set is positioned on the other side of the intended cut line C Lon the second side. For simplicity, only four struts from each set 5228a, 5228b, 5228c, 5228d, 5230a, 5230b, 5230c, 5230d are shown. While the two sets of struts can have various configurations, in the illustrated embodiment, the two sets of struts are identical, and thus for each set, the first strut 5228a, 5230a (e.g., the innermost row of struts) has a first height, the second strut 5228b, 5228b (e.g., the innermost middle row of struts) has a second height that is greater than the first height, the third strut 5228c, 5230c (e.g., the outermost middle row of struts) has a third height that is greater than the second height, and the fourth strut 5228d, 5230d (e.g., the outermost row of struts) has a fourth height that is greater than the second height. Thus, the uncompressed thickness (e.g., along the width of the adjunct, in the y-direction) of the first lattice structure 5224 varies laterally with respect to the longitudinal axis L A (e.g., extending in the z-direction) of the longitudinal adjunct 5206. These lateral variations can be scaled along the curved top surface or deck surface 5208a of the cartridge 5208, such that a portion of the cartridge-contacting surface 5220 of the adjunct 5206 formed by the bottom surface 5224b of the first lattice structure 5224 is complementary in shape to the curved top surface or deck surface 5208a (e.g., concave configuration) of the cartridge 5208. Thus, the thickness variations of the first lattice structure 5224 can conform to the variations of the top surface or deck surface 5208a. A ) extending in the z-direction) of the longitudinal adjunct 5206. These lateral variations can be scaled along the curved top surface or deck surface 5208a of the cartridge 5208, such that a portion of the cartridge-contacting surface 5220 of the adjunct 5206 formed by the bottom surface 5224b of the first lattice structure 5224 is complementary in shape to the curved top surface or deck surface 5208a (e.g., concave configuration) of the cartridge 5208. Thus, the thickness variations of the first lattice structure 5224 can conform to the variations of the top surface or deck surface 5208a.

[0365] As further shown, FIG. 52A to minimize the impact of the first lattice structure 5224 on the densification of the adjunct 5206, the first lattice structure 5224 can be designed in a manner that it does not overlap with the staples 5214a, 5214a, 5214c, 5216a, 5216b, 5216c. For example, in the illustrated embodiment, none of the struts 5228a, 5228b, 5228c, 5228d, 5230a, 5230b, 5230c, 5230d overlap with any of the staples 5214a, 5214b, 5214c, 5216a, 5216b, 5216c, and thus the first lattice structure 5224 will not be captured by the staples during deployment. Thus, when the adjunct 5206 is sutured to tissue, the pressure applied by the adjunct 5206 to the sutured tissue can depend entirely or substantially entirely on the compression characteristics of the second lattice structure 5226.

[0366] In some embodiments, the wall thickness and height of each repeating cell can vary among other repeating cells. For example, FIG. 53Another example embodiment of an adjunct 5300 releasably retained on a top surface or deck surface 5302a (e.g., a staple cartridge surface facing the anvil) of a staple cartridge 5302 is shown. The staple cartridge 5302 is similar to the staple cartridge 5108 in FIGS. 51A-51B U.S. Patent No. 10,662,643, the disclosure of which is herein incorporated by reference in its entirety, except for the differences described below, and therefore is not described in detail herein. As shown in FIG. 53 FIG. 7, only half (e.g., the right half) of the adjunct 5300 is shown on the staple cartridge 5302 with three rows of staples 5304, 5306, 5308 partially disposed therein, with the innermost row of staples 5304 having the smallest staple height and the outermost row of staples 5308 having the largest staple height. As described above, the difference in staple height can contribute to the overall compression behavior of the adjunct when stapled to tissue.

[0367] While the adjunct 5300 can have various configurations, the adjunct 5300 is formed from interconnected repeating cells that are disposed in two groups of three longitudinal arrays, with the first group positioned on one side of an intended cut line C L of the adjunct 5300 and the second group (not shown) positioned on a second side of the intended cut line C L of the adjunct 5300. Since both groups are identical, only one repeating cell 5310, 5312, 5314 of the three longitudinal arrays of the first group is shown in FIG. 53 FIG. 7.

[0368] The repeating cells 5310, 5312, 5314 can have a variety of configurations. In this illustrated embodiment, the repeating cells 5310, 5312, 5314 are similar in overall shape, except for the wall thickness and height vary among the three repeating cells 5310, 5312, 5314. As shown, each repeating cell has a varying height (e.g., in the X-direction) from their respective outermost top surfaces 5310a, 5312a, 5314a (laterally offset in the y-direction and aligned relative to one another) to their respective outermost bottom surfaces 5310b, 5312b, 5314b, and thus for simplicity, the minimum height H 1A and the maximum height H 1B of the repeating cell 5310, the minimum height H 2A and the maximum height H 2B of the repeating cell 5312, and the minimum height H 3A and the maximum height H 3B of the repeating cell 5314 are shown.

[0369] As shown in the figure, a portion of the top surface 5300a of the appendage 5300 is generally planar and therefore includes generally planar surfaces 5316 (e.g., each surface in the y-direction), with non-planar surfaces 5318 extending therebetween. The top surface 5300a defines the tissue contact surface 5320 of the appendage 5300, and thus the tissue contact surface 5320 is formed by planar surfaces 5316 and non-planar surfaces 5318. Since the generally planar surfaces 5316 and non-planar surfaces 5318 of the top surface 5300a (and therefore the tissue contact surface 5320) alternate along the width of the appendage 5300 (extending in the y-direction), thus in... FIG. 51A The anvil 5102 in the anvil and the appendage 5300 create a consistent tissue gap (e.g., alternating between a generally uniform tissue gap and a variable tissue gap). In this illustrated embodiment, each generally uniform tissue gap occurs at the tissue-compression surface (e.g., FIG. 51A The tissue-compression surface 5112 of the anvil 5102 is between the generally planar surface 5316 of the tissue contact surface 5320. Variable tissue gaps occur between the tissue-compression surface (e.g., ...) FIG. 51A Between the tissue-compression surface 5112 of the anvil 5102 and the non-planar surface 5318 of the tissue contact surface 5320 (which extends between adjacent cells of the appendage 5300). Those skilled in the art will understand that the length of the generally uniform and variable tissue gap (extending in the x-direction) can depend at least on the structural configuration of the tissue contact surface, and therefore on the structural configuration of the appendage.

[0370] Furthermore, the wall thickness and height between at least two repeating cells can vary, thus resulting in different compression ratios. In this illustrated embodiment, the wall thickness W from the first repeating cell 5310 (e.g., the innermost repeating cell) to the third repeating cell 5314 (e.g., the outermost repeating cell) is... T And H increases. That is to say, the wall thickness W of the first repeating cell 5310. T1 The wall thickness W with height H1 less than the second repeating cell 5312 (e.g., the middle repeating cell). T2 and height H2, and wall thickness W of the second repeating grid 5312. T2 The height H2 is less than the wall thickness W of the third repeating cell 5314. T3and a height H3. Thus, the compression ratio decreases from the first repeating cell 5310 to the third repeating cell 5314. That is, the first compression ratio of the first repeating cell 5310 is greater than each of the second and third compression ratios of the second repeating cell 5312 and the third repeating cell 5314, and the second compression ratio is greater than the third compression ratio. Thus, these compression ratios will result in a varying overall compression ratio of the adjunct 5300 such that when the adjunct is stapled to tissue with staples 5304, 5306, 5308 having different staple heights (e.g., the innermost staples 5304 having the smallest top height and the outermost staples 5308 having the largest top height), the adjunct 5300 is configured to apply a generally uniform pressure to the stapled tissue for a predetermined period of time.

[0371] As described above, the adjunct can include a combination of non-stent based cells and stent based cells and / or spaced stents. For example, FIG. 54 An exemplary embodiment of an adjunct 5400 is shown releasably retained on a top or deck surface 5402a (e.g., an anvil facing cartridge surface) of a staple cartridge 5402. The staple cartridge 5402 is similar to the cartridge 200 in FIGS. 1-2C and thus the common features are not described in detail herein. As shown in FIG. 54, only one half (e.g., the left half) of the adjunct 5400 is shown on the staple cartridge 5402 with three longitudinal rows 5303a, 5303b, 5303c of substantially uniform staples 5404a, 5404b, 5404c disposed thereon. FIG. 54

[0372] While the adjunct 5400 can have various configurations, as shown, the adjunct has an internal lattice structure 5406 formed of two sets of two longitudinal arrays of repeating non-stent based cells, with a first set positioned on one side of an intended cut line C L of the adjunct 5400 and a second set (not shown) positioned on a second side of the intended cut line C L of the adjunct 5400. Since both sets are identical, only one repeating cell 5408, 5410 of the two longitudinal arrays is shown in FIG. 54 Additionally, the adjunct 5400 includes a first and second external lattice structure (only the first external lattice structure 5412 is shown) that are structurally similar and positioned on opposite sides of the internal lattice structure. While only the first external lattice structure 5412 and the first and second repeating cells 5408, 5410 of the adjunct 5400 are shown, one skilled in the art will understand that the following discussion applies to the second lattice structure and the repeating cells of the second set of longitudinal arrays as well.

[0373] ​The first repeating cell 5408 and the second repeating cell 5410 can have a variety of configurations. In the illustrated embodiment, the repeating cells 5408, 5410 are generally uniform (e.g., nominally identical within manufacturing tolerances) and structurally similar to the repeating cells 810 in FIGS. 9A-9B , and thus the common features are not described in detail herein. As shown, the first repeating cell 5408 and the second repeating cell 5410 are oriented similar to the repeating cells 4516 in FIGS. 45A-45C , and thus the internal lattice structure 5406 can have a configuration similar to the adjunct 4500 structure in FIGS. 45A-45C . Thus, the repeating cells 5408, 5410 are oriented in a manner (e.g., in a repeating pattern) that coincides with the locations of the staples in one or more of the staple rows that can overlap the internal lattice structure 5406. As further shown, the first external lattice structure 5412 includes strut-based cells (only two of the lattices 5414a, 5414b are shown completely). While the strut-based cells can have a variety of configurations, the first strut-based cell 5414a has a triangular configuration and the second strut-based cell 5414b has an inverted triangular configuration. As further shown, a portion of the second strut-based cell 5414b crosses over the first strut-based cell 5414a.

[0374] As shown, the lattice structures 5406, 5412 are adjacent and laterally offset from one another relative to the longitudinal axis L A of the adjunct 5400 (e.g., extending in the z-direction L A ). That is, the first external lattice structure 5412 is positioned directly adjacent to the first longitudinal side 5406a of the internal lattice structure 5406. In addition, the internal lattice structure 5406 overlaps the first and second staple rows 5403a, 5303b (e.g., the innermost and middle staple rows), and thus the first and second staples 5404a, 5404b, respectively, and the first external lattice structure 5412 overlaps the third staple row 5404c (e.g., the outermost staple row), and thus the third staples 5404c. In the illustrated embodiment, the first repeating cells 5408 of the first longitudinal array and the second repeating cells 5410 of the second longitudinal array are staggered relative to one another, and thus are oriented in a manner (e.g., a repeating pattern) that coincides with the locations of the first and second staples 5404a, 5404b.

[0375] This alignment of the lattice structures 5406, 5412 relative to the first 5404a, second 5404b, and third 5404c staples, in combination with the different structural configurations of the lattice structures 5406, 5412, can result in at least two different stress-strain curves when the adjunct is sutured to tissue. Given the orientation of the first repeating cell and the second repeating cell relative to the first and second staples, the resulting stress-strain curves of the adjunct at the first and second staples can be the same or substantially the same. The compression behavior of the adjunct 5300 at each of the first 5404a, second 5404b, and third 5404c staples is schematically illustrated in FIG. 55 where S1 represents the stress-strain curve of the adjunct at the first staple 5404a, S2 represents the stress-strain curve of the adjunct at the second staple 5404b, and S3 represents the stress-strain curve at the third staple 5404c. In this schematic, the stress-strain curve S1 at the first staple and the stress-strain curve S2 at the second staple are shown as identical curves. Those skilled in the art will appreciate that the stress-strain curves at each staple can vary.

[0376] Attachment system

[0377] Generally, the adjunct systems described herein can include at least two different adjuncts, where each adjunct is configured to experience a respective strain within a respective range of strain under a respective applied stress that is within a range of about 30 kPa to 90 kPa. In some embodiments, the at least two respective ranges of strain can at least partially overlap, while in other embodiments, the at least two respective ranges do not overlap. Additionally or alternatively, the combination of the respective ranges of strain can result in a combined range of at least 0.1 to 0.9. In other embodiments, the combined range can be about 0.1 to 0.8, about 0.1 to 0.7, about 0.1 to 0.6, about 0.1 to 0.5, about 0.1 to 0.4, about 01. to 0.3, about 0.2 to 0.8, about 0.2 to 0.7, about 0.3 to 0.7, about 0.3 to 0.8, about 0.3 to 0.9, about 0.4 to 0.9, about 0.4 to 0.8, about 0.4 to 0.7, about 0.5 to 0.8, or about 0.5 to 0.9. While the adjunct systems can include at least two different adjuncts, for simplicity, the following description is with respect to adjunct systems having only a first adjunct and a second adjunct. However, those skilled in the art will appreciate that the following discussion also applies to additional adjuncts of the adjunct system.

[0378] In some embodiments, the adjunct system can include a first adjunct and a second adjunct, where the first adjunct experiences a first range of strain when under an applied stress in the range of about 30 kPa to 90 kPa, and the second adjunct experiences a second range of strain when under an applied stress in the range of about 30 kPa to 90 kPa. The stress-strain response of each adjunct depends at least on the structural configuration and constituent composition of each adjunct. Accordingly, the first adjunct and the second adjunct can be customized to achieve a desired strain response over the applied stress and / or range of applied stresses. For example, in some embodiments, the first adjunct can be configured such that it experiences a strain in a first range of about 0.2 to 0.5 when under an applied stress in the range of about 60 kPa to 90 kPa, and the second adjunct can be configured such that it experiences a strain in a second range of about 0.3 to 0.7 when under an applied stress in the range of about 40 kPa to 70 kPa. In another embodiment, the first adjunct can be configured such that it experiences a strain in a first range of about 0.1 to 0.7 when under an applied stress in the range of about 30 kPa to 90 kPa, and the second adjunct can be configured such that it experiences a strain in a second range of about 0.3 to 0.9 when under an applied stress in the range of about 30 kPa to 90 kPa. In another embodiment, the first adjunct can be configured such that it experiences a strain in a first range of about 0.2 to 0.6 when under an applied stress in the range of about 30 kPa to 90 kPa, and the second adjunct can be configured such that it experiences a strain in a second range of about 0.4 to 0.8 when under an applied stress in the range of about 30 kPa to 90 kPa. In another embodiment, the first adjunct can be configured such that it experiences a strain in a first range of about 0.1 to 0.7 when under an applied stress in the range of about 40 kPa to 80 kPa, and the second adjunct can be configured such that it experiences a strain in a second range of about 0.2 to 0.8 when under an applied stress in the range of about 30 kPa to 90 kPa.

[0379] The first adjunct and the second adjunct can have a variety of structural configurations. For example, the first adjunct can have a configuration similar to any one of the example adjuncts described herein, and the second adjunct can have a different configuration than the first adjunct and similar to another one of the example adjuncts described herein. In some embodiments, the first adjunct can be a non-strut-based adjunct, and the second adjunct can be another non-strut-based adjunct or a strut-based adjunct described herein. In other embodiments, the first adjunct can be a strut-based adjunct, and the second adjunct can be another strut-based adjunct or a non-strut-based adjunct.

[0380] In some embodiments, the first adjunct has a first internal structure formed from a first plurality of repeating, interconnected unit cells, and the second adjunct has a second internal structure formed from a second plurality of repeating, interconnected unit cells. In certain embodiments, the first plurality of repeating, interconnected unit cells can be formed from a first material, and the second plurality of repeating, interconnected unit cells can be formed from a second material different from the first material. The first material and the second material can be any of the materials described herein and in more detail below. Additionally or alternatively, each unit cell of the first plurality of repeating, interconnected unit cells has a first geometric shape, and each unit cell of the second plurality of repeating, interconnected unit cells has a second geometric shape different from the first geometric shape.

[0381] In some embodiments, each unit cell of at least one of the first plurality of repeating, interconnected unit cells and the second plurality of repeating, interconnected unit cells is a triply periodic minimal surface structure (e.g., a Schwarz P structure). In one embodiment, each unit cell of the first plurality of repeating, interconnected unit cells is a first triply periodic minimal surface structure, and each unit cell of the second plurality of repeating, interconnected unit cells is a second triply periodic minimal surface structure different from the first triply periodic minimal surface structure. For example, the first triply periodic minimal surface structure and the second triply periodic minimal surface structure can differ in geometric shape (e.g., shape, size (e.g., height, wall thickness, etc.), or a combination thereof).

[0382] In some embodiments, each cell of the first plurality of repeatedly interconnected unit cells can include a first top portion, a first bottom portion, and a first spaced strut interconnecting the first top portion and the first bottom portion, the first top portion formed from a first plurality of struts defining a first plurality of openings therebetween, the first bottom portion formed from a second plurality of struts defining a second plurality of openings therebetween. In such embodiments, each cell of the second plurality of repeatedly interconnected unit cells can be a Schwarz-P structure. In other embodiments, each cell of the second plurality of repeatedly interconnected unit cells can include a second top portion, a second bottom portion, and a second spaced strut interconnecting the second top portion and the second bottom portion, the second top portion formed from a third plurality of struts defining a third plurality of openings therebetween, the second bottom portion formed from a fourth plurality of struts defining a fourth plurality of openings therebetween.

[0383] Materials

[0384] The adjuncts described herein can be formed from one or more polymers, such as bioabsorbable polymers, non-bioabsorbable polymers, bioresorbable polymers, or any combination thereof. For clarity only, “polymer” as used herein can be understood to encompass one or more polymers, including one or more macromers. Non-limiting examples of suitable polymers include polylactide (PLA), polycaprolactone (PCL), polyglycolide (PGA), polydioxanone (PDO), polytrimethylenecarbonate (PTMC), polyethylene glycol (PEG), polyethylene diglycolate (PEDG), polypropylene fumarate (PPF), poly(ethoxyethylene diglycolate), poly(ether ester) (PEE), poly(amino acid), poly(epoxide carbonate), poly(2-oxo-propylene carbonate), poly(lactic diol citrate), poly(methacrylic anhydride), and poly(N-isopropylacrylamide), copolymers of any one thereof, or any combination thereof. Non-limiting examples of suitable copolymers include random copolymers such as PLGA-PCL, block copolymers such as poly(lactide-co-glycolide) (PLGA), tri-block copolymers such as PLGA-PCL-PLGA or PLGA-PEG-PLGA, or any combination thereof. Additional non-limiting examples of suitable polymers are disclosed in, for example, U.S. Patent Nos. 9,770,241; 9,873,790; 10,085,745; and 10,149,753; and U.S. Patent Publication No. 2017 / 0355815, each of which is incorporated herein by reference in its entirety.

[0385] In some embodiments, the polymer can be formed from a resin. Generally, the resins described herein can be suitable for use in additive manufacturing techniques such as bottom-up and top-down stereolithography, (b) to produce a bioresorbable adjunct, and / or (c) to produce a flexible or elastic adjunct (e.g., at about 25 °C, about 37 °C, and / or any temperature therebetween).

[0386] In some embodiments, the polymer can be formed from a photopolymerizable resin that includes an oligomeric prepolymer. The oligomeric prepolymer can be linear or branched (e.g., a “star” oligomer, such as a tri-arm oligomer). Non-limiting examples of suitable end groups for such oligomeric prepolymers include: acrylate, methacrylate, fumarate, vinyl carbonate, methyl ester, ethyl ester, and the like. Non-limiting examples of suitable components of exemplary resins that can be used to form the polymer, and thus the adjuncts provided herein, are listed in Table 2 below. The components in each column of Table 2 can be combined in any combination with the components of the other columns.

[0387] Table 2. Exemplary resin compositions

[0388]

[0389] While various types of resins can be used to form the polymer, in some embodiments, the polymer is formed from a resin that is based on a bioabsorbable polyester oligomer (e.g., a methacrylate-terminated oligomer having bioabsorbable polyester linkages). For example, the bioabsorbable polyester oligomer can be present in an amount of about 5% to 90%, 5% to 80%, about 10% to 90%, or about 10% to 80% by weight of the resin. Unlike conventional resins (e.g., polycaprolactone dimethacrylate-based resins and poly(D,L-lactide) dimethacrylate-based resins), this resin can form an adjunct having rubber-like elastic behavior, short-term retention of mechanical properties (e.g., 1 month or less), and / or long-term full absorption (e.g., within a period of about 4 to 6 months) at physiological temperatures.

[0390] In some embodiments, the oligomer can include a linear oligomer. Alternatively or additionally, the oligomer can include a branched oligomer (e.g., a star oligomer, such as a tri-arm oligomer).

[0391] In some embodiments, the bioabsorbable polyester oligomers described herein are bioabsorbable oligomers having methacrylate end groups. Such oligomers generally include bioerodible ester linkages between components such as caprolactone, lactide, glycolide trimethylene carbonate, dioxanone, and fumarate propylene glycol monomers in an ABA block, BAB block, CBC block, BCB block, AB random composition, BC random composition, homopolymer, or any combination thereof, where: A = poly(lactide) (PLA), poly(glycolide) (PGA), poly(lactide-co-glycolide) (PLGA), or polypropylene fumarate (PPF), B = poly(caprolactone) (PCL), poly(lactide-co-caprolactone) (PLACL), poly(glycolide-co-caprolactone) (PGACL), poly(trimethylene carbonate) (PTMC), or poly(caprolactone-co-lactide) (PCLLA), and C = polydioxanone (PDO). The molecular weight (Mn) of the copolymer in linear or star structures can be about 2 kilodaltons to 6 kilodaltons, about 2 kilodaltons to 10 kilodaltons, about 2 kilodaltons to 15 kilodaltons, about 2 kilodaltons to 20 kilodaltons, about 2 kilodaltons to 50 kilodaltons, about 5 kilodaltons to 6 kilodaltons, about 5 kilodaltons to 10 kilodaltons, about 5 kilodaltons to 15 kilodaltons, about 5 kilodaltons to 20 kilodaltons, about 5 kilodaltons to 50 kilodaltons, about 10 kilodaltons to 15 kilodaltons, about 10 kilodaltons to 20 kilodaltons, or about 10 kilodaltons to 50 kilodaltons. The monomers used to make such oligomers can optionally be introduced with branching, for example, to enhance elasticity, one example being gamma-methyl-epsilon-caprolactone and gamma-ethyl-epsilon-caprolactone.

[0392] In some embodiments, the lactide can include L-lactide, D-lactide, or a mixture thereof (e.g., D,L-lactide). For example, in some embodiments having a PLA block, L-lactide can be used for better regularity and higher crystallinity.

[0393] In some embodiments, the oligomers can include ABA blocks, BAB blocks, CBC blocks, or BCB blocks in linear and / or branched (e.g., star or triarm) form.

[0394] In some embodiments, A can be: (i) poly(lactide); (ii) poly(glycolide); (iii) poly(lactide-co-glycolide) comprising lactide:glycolide in a molar ratio of 90:10 to 55:45 (e.g., lactide-rich ratio), 45:55 to 10:90 lactide:glycolide (e.g., glycolide-rich ratio), or 50:50 lactide:glycolide; or any combination thereof. In such embodiments, the oligomer can be in linear and / or branched (e.g., star or triarm) form. In some embodiments, D,L-lactide mixtures can be used to make PLGA random copolymers.

[0395] In some embodiments, B can be: (i) polycaprolactone; (ii) polytrimethylene carbonate; polytrimethylene carbonate; (iii) poly(caprolactone-co-lactide) comprising caprolactam:lactide in a molar ratio of 95:5 to 5:95; or any combination thereof.

[0396] In some embodiments, the molecular weight (Mn) of A (PLA, PGA, PLGA, PPF, or any combination thereof) can be about 1 kilodalton to 4 kilodaltons, about 1 kilodalton to 6 kilodaltons, about 1 kilodalton to 10 kilodaltons, about 2 kilodaltons to 4 kilodaltons, about 2 kilodaltons to 6 kilodaltons, or about 2 kilodaltons to 10 kilodaltons; and the molecular weight (Mn) of B (PCL, PLACL, PGACL, PTMC, PCLLA, or any combination thereof) can be about 1 kilodalton to 4 kilodaltons, about 1 kilodalton to 6 kilodaltons, about 1 kilodalton to 10 kilodaltons, about 1 kilodalton to 50 kilodaltons, about 1.6 kilodaltons to 4 kilodaltons, about 1.6 kilodaltons to 6 kilodaltons, about 1.6 kilodaltons to 10 kilodaltons, or about 1.6 kilodaltons to 50 kilodaltons.

[0397] The resin can also include additional components, such as additional crosslinking agents, non-reactive diluents, photoinitiators, reactive diluents, fillers, or any combination thereof.

[0398] In some embodiments, the resin can include an additional crosslinking agent. For example, the additional crosslinking agent can be present in an amount of about 1% to 5%, about 1% to 10%, about 2% to 5%, or about 2% to 10% by weight of the resin. Any suitable additional crosslinking agent can be used, including bioabsorbable crosslinking agents, non-absorbable crosslinking agents, or any combination thereof. Non-limiting examples of suitable bioabsorbable crosslinking agents include: divinyl adipate (DVA), poly(caprolactone) trimethacrylate (PCLDMA, e.g., at a molecular weight MW of about 950 to 2400 daltons), and the like. Non-limiting examples of suitable non-absorbable crosslinking agents include: trimethylolpropane trimethacrylate (TMPTMA), poly(propylene glycol) dimethacrylate (PPGDMA), poly(ethylene glycol) dimethacrylate (PEGDMA), and the like.

[0399] In some embodiments, the resin can include a non-reactive diluent. For example, the non-reactive diluent can be present in an amount of about 1% to 70%, about 1% to 50%, about 5% to 70%, or about 5% to 50% by weight of the resin. Non-limiting examples of non-reactive diluents include: dimethylformamide, dimethylacetamide, N-methyl pyrrolidone (NMP), dimethyl sulfoxide, cyclic carbonates (e.g., propylene carbonate), diethyl adipate, methyl ether ketone, ethanol, acetone, or any combination thereof.

[0400] In some embodiments, the resin can include a photoinitiator. For example, the photoinitiator can be present in an amount of about 0.1% to 4%, about 0.1% to 2%, about 0.2% to 4%, or about 0.2% to 2% by weight of the resin. The photoinitiator included in the resin can be any suitable photoinitiator. Non-limiting examples of suitable photoinitiators include: Type I and Type II photoinitiators, and UV photoinitiators (e.g., phenones (e.g., diethoxy phenone), phosphine oxides (e.g., diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, phenyl bis(2,4,6-trimethylbenzoyl) phosphine oxide (PPO)), 369) and the like. Additional exemplary photoinitiators can be found in U.S. Patent No. 9,453,142, which is incorporated by reference herein in its entirety.

[0401] In one embodiment, the resin can include: a bioabsorbable polyester oligomer, which can be present in an amount of about 5% to 90%, 5% to 80%, about 10% to 90%, or about 10% to 80% by weight of the resin; a non-reactive diluent, which can be present in an amount of about 1% to 70%, about 1% to 50%, about 5% to 70%, or about 5% to 50% by weight of the resin; and a photoinitiator, which can be present in an amount of about 0.1% to 4%, about 0.1% to 2%, about 0.2% to 4%, or about 0.2% to 2% by weight of the resin.

[0402] In some embodiments, the resin can include a reactive diluent (including di- and tri-functional reactive diluents). For example, the reactive diluent can be present in an amount of about 1% to 50%, about 1% to 40%, about 5% to 50%, or about 5% to 40% by weight of the resin. Non-limiting examples of reactive diluents include: acrylates, methacrylates, styrene, vinyl amides, vinyl ethers, vinyl esters, polymers containing any one or more of the foregoing, or any combination thereof (e.g., acrylonitrile, styrene, divinylbenzene, vinyltoluene, methyl acrylate, ethyl acrylate, butyl acrylate, methyl (meth)acrylate, isobornyl acrylate (IBOA), isobornyl methacrylate (IBOMA), alkyl ethers of mono-, di-, or tri-ethylene glycol acrylate or methacrylate, fatty alcohol acrylate or methacrylate such as lauryl (meth)acrylate, and mixtures thereof).

[0403] In one embodiment, the resin can include: a bioabsorbable polyester oligomer, which can be present in an amount of about 5% to 90%, about 5% to 80%, about 10% to 90%, or about 10% to 80% by weight of the resin; a non-reactive diluent, which can be present in an amount of about 1% to 70%, about 1% to 50%, about 5% to 70%, or about 5% to 50% by weight of the resin; a photoinitiator, which can be present in an amount of about 0.1% to 4%, about 0.1% to 2%, about 0.2% to 4%, or about 0.2% to 2% by weight of the resin; and a reactive diluent, which can be present in an amount of about 1% to 50%, about 1% to 40%, about 5% to 50%, or about 5% to 40% by weight of the resin.

[0404] In some embodiments, the resin can include a filler. For example, the filler can be present in an amount of about 1% to 50%, about 1% to 40%, about 2% to 50%, or about 2% to 40% by weight of the resin. Any suitable filler can be used in connection with the present application, including but not limited to bioabsorbable polyester particles, sodium chloride particles, calcium triphosphate particles, sugar particles, and the like.

[0405] In one embodiment, the resin can include: a bioabsorbable polyester oligomer, which can be present in an amount of about 5% to 90%, about 5% to 80%, about 10% to 90%, or about 10% to 80% by weight of the resin; a non-reactive diluent, which can be present in an amount of about 1% to 70%, about 1% to 50%, about 5% to 70%, or about 5% to 50% by weight of the resin; a photoinitiator, which can be present in an amount of about 0.1% to 4%, about 0.1% to 2%, about 0.2% to 4%, or about 0.2% to 2% by weight of the resin; a reactive diluent, which can be present in an amount of about 1% to 50%, about 1% to 40%, about 5% to 50%, or about 5% to 40% by weight of the resin; and a filler, which can be present in an amount of about 1% to 50%, about 1% to 40%, about 2% to 50%, or about 2% to 40% by weight of the resin.

[0406] Additionally, depending on the particular use of the adjunct, in some embodiments, the resin can have additional components. For example, in certain embodiments, the resin can include one or more additional components, which can be present in an amount of about 0.1% to 10% by weight, about 0.1% to 10% by weight, about 1% to 20% by weight, or about 1% to 10% by weight of the resin. Non-limiting examples of suitable additional components include: pigments, dyes, diluents, active compounds or pharmaceutical compounds, detectable compounds (e.g., fluorescent, phosphorescent, radioactive), proteins, peptides, nucleic acids (DNA, RNA) such as siRNA, sugars, etc., including any combination thereof.

[0407] In some embodiments, the resin can include a non-reactive pigment or dye that absorbs light, particularly UV light. Non-limiting examples of suitable non-reactive pigments or dyes include: (i) titanium dioxide (e.g., present in an amount of about 0.05% to 5%, about 0.05% to 1%, about 0.1% to 1%, or about 0.1% to 5% by weight of the resin), (ii) carbon black (e.g., present in an amount of about 0.05% to 5%, about 0.05% to 1%, about 0.1% to 1%, or about 0.1% to 5% by weight of the resin), and / or (iii) an organic UV absorber such as a hydroxybenzophenone, a hydroxyphenylbenzotriazole, an oxanilide, an oxalylamide, a thioxanthone, a hydroxyphenyltriazine, and / or a benzotriazole UV absorber (e.g., Mayzo BLS1326) (e.g., present in an amount of about 0.001% to 1%, 0.001% to 2%, about 0.001% to 4%, about 0.005% to 1%, about 0.005% to 2%, or about 0.005% to 4% by weight of the resin). Additional exemplary non-reactive pigments or dyes are disclosed in U.S. Patent Nos. 3,213,058, 6,916,867, 7,157,586, and 7,695,643, each of which is incorporated herein by reference in its entirety.

[0408] In some embodiments, the resin can include: (a) (meth)acrylate-terminated bioresorbable polyester oligomers present in an amount of about 5% to 80%, about 5% to 90%, about 10% to 80%, or about 10% to 90% by weight of the resin; (b) non-reactive diluent present in an amount of about 1% to 50%, about 1% to 70%, about 5% to 50%, or about 5% to 70% by weight of the resin; and (c) photoinitiator present in an amount of about 0.1% to 2%, about 0.1% to 4%, about 0.2% to 2%, or about 0.2% to 4% by weight of the resin. In such embodiments, the resin can also include (d) reactive diluent present in an amount of about 1% to 40%, about 1% to 50%, about 5% to 40%, or about 5% to 50% by weight of the resin; (e) filler present in an amount of about 1% to 40%, about 1% to 50%, about 2% to 40%, or about 2% to 50% by weight of the resin; (f) additional ingredients (e.g., active agents, detectable groups, pigments or dyes, etc.) present in an amount of about 0.1% to 10%, about 0.1% to 20%, about 1% to 10%, or about 1% to 20% by weight of the resin; and / or (g) additional crosslinking agent (e.g., trimethylolpropane trimethacrylate (TMPTMA)) present in an amount of about 1% to 5%, about 1% to 10%, about 2% to 5%, or about 2% to 10% by weight of the resin.

[0409] In some embodiments, the resin can include:

[0410] (a) (meth)acrylate-terminated linear or branched bioresorbable polyester oligomers in ABA blocks, BAB blocks, CBC blocks, or BCB blocks, present in an amount of about 5% to 80%, about 5% to 90%, about 10% to 80%, or about 10% to 90% by weight of the resin, wherein: A is poly(lactide) (PLA), poly(glycolide) (PGA), poly(lactide-co-glycolide) (PLGA), or any combination thereof, wherein the PLGA contains lactide:glycolide in a molar ratio of 90:10 to 60:40 or 40:60 to 10:90, and the molecular weight (Mn) of A is about 1 kilodalton to 4 kilodaltons, about 1 kilodalton to 10 kilodaltons, about 2 kilodaltons to 4 kilodaltons, or about 2 kilodaltons to 10 kilodaltons; B is poly(caprolactone) (PCL, PTMC, and PCLLA), poly(lactide-co-caprolactone) (PLACL), poly(glycolide-co-caprolactone) (PGACL), poly(trimethylenecarbonate) (PTMC), and the molecular weight (Mn) of B is about 1 kilodalton to 4 kilodaltons, about 1 kilodalton to 10 kilodaltons, about 1.6 kilodaltons to 4 kilodaltons, or about 1.6 kilodaltons to 10 kilodaltons; and C is polydioxanone (PDO), and the molecular weight (Mn) of C is about 1 kilodalton to 4 kilodaltons, about 1 kilodalton to 10 kilodaltons, about 2 kilodaltons to 4 kilodaltons, or about 2 kilodaltons to 10 kilodaltons;

[0411] (b) propylene glycol carbonate present in an amount of about 1% to 50%, about 1% to 70%, about 5% to 50%, or about 5% to 70% by weight of the resin;

[0412] (c) a photoinitiator present in an amount of about 0.1% to 2%, about 0.1% to 4%, about 0.2% to 2%, or about 0.2% to 4% by weight of the resin;

[0413] (d) optionally a reactive diluent present in an amount of about 1% to 40%, about 1% to 50%, about 5% to 40%, or about 5% to 50% by weight of the resin; and

[0414] (e) optionally a filler present in an amount of about 1% to 40%, about 1% to 50%, about 2% to 40%, or about 2% to 50% by weight of the resin.

[0415] Manufacturing method

[0416] The non-fibrous adjuncts described herein can be formed from a matrix comprising at least one melt-bioabsorbable polymer, and thus can be formed using any additive manufacturing process. In some embodiments, the additive manufacturing process can be continuous liquid interface generation (CLIP) that involves the use of ultraviolet light to cure a liquid plastic resin. Details of the CLIP process are disclosed in, for example, U.S. Patent Nos. 9,211,678; 9,205,601; and 9,216,546; U.S. Patent Publication Nos. 2017 / 0129169; 2016 / 0288376; 2015 / 0360419; 2015 / 0331402; 2017 / 0129167; 2018 / 0243976; 2018 / 0126630; and 2018 / 0290374; J. Tumbleston et al., Continuous liquid interface production of 3D Objects, Science 347, pp. 1349-1352 (2015); and R. Janusziewcz et al., Layerless fabrication with continuous liquid interface production, Proc. Natl. Acad. Sci. USA 113, pp. 11703-11708 (2016); each of which is incorporated herein by reference in its entirety. Non-limiting examples of other additive manufacturing equipment and methods that can be used to form the non-fibrous adjuncts described herein (and thus to form a matrix comprising at least one melt-bioabsorbable polymer) can include bottom-up and top-down additive manufacturing methods (e.g., U.S. Patent Nos. 5,236,637; 5,391,072; 5,529,473; 7,438,846; 7,892,474; and 8,110,135 and U.S. Patent Publication Nos. 2013 / 0292862 and 2013 / 0295212, each of which is incorporated herein by reference in its entirety), as well as fused deposition modeling (e.g., heating a thermoplastic filament and extruding layers of the molten filament layer-by-layer), material jetting, 2-photon polymerization, and holographic multi-focal polymerization as understood by one of skill in the art.

[0417] In certain embodiments, one or more post-processing steps can be performed after the additive manufacturing process. For example, in some embodiments, the one or more post-processing steps can include washing the adjunct (e.g., in an organic solvent such as acetone, isopropyl alcohol, a glycol ether such as dipropylene glycol methyl ether or DPM), wiping the adjunct (e.g., with an absorbent material, with compressed gas or air knife, etc.), centrifuging to separate residual resin, extracting residual solvent, additional curing such as by flood exposure with ultraviolet light, etc. to, for example, further react unpolymerized components of the adjunct, drying the adjunct (e.g., under vacuum) to remove extraction solvent therefrom, or any combination thereof. The one or more post-processing steps can cause the adjunct to shrink, and thus, in some embodiments, the adjunct can be produced in a magnified form to offset such shrinkage.

[0418] In other embodiments, the non-fibrous adjunct can be formed, in part or in whole, using any suitable non-additive manufacturing process such as, for example, injection molding, foaming, and molding processes as understood by one of skill in the art.

[0419] The stapling assembly can be manufactured in various ways. For example, in some embodiments, as discussed above, the non-fibrous adjunct can be releasably attached to the staple cartridge by placing the cartridge-contacting surface of the adjunct against a surface of the cartridge (e.g., a surface facing the anvil, for example, a top surface or deck surface) so as to insert the at least one attachment feature of the adjunct into the at least one surface feature (e.g., a recessed channel) of the cartridge (see, e.g., FIGS. 19A-26C 、 FIGS. 37A-39B and FIGS. 41A-41C ). Alternatively or additionally, as discussed above, the non-fibrous adjunct can be configured to receive one or more cartridge protrusions (e.g., staple pocket protrusions) and / or staple legs (see, e.g., FIGS. 45A-46B ). Additional details regarding surface features and other exemplary surface features can be found in U.S. Patent No. 2016 / 0106427, which is incorporated by reference herein in its entirety. Alternatively or additionally, as discussed above, the non-fibrous adjunct can include an outer layer in the form of an adhesive film for releasably retaining the adjunct on the staple cartridge (see, e.g., FIG. 40 ). Additional details regarding adhesive films and other attachment methods can be found in U.S. Patent No. 10,349,939, which is incorporated by reference herein in its entirety.

[0420] The adjuncts and methods can be further understood with the following non-limiting examples.

[0421] Examples

[0422] Example 1-3: Preparation of difunctional methacrylate (MA) terminated polyester oligomers

[0423] Examples 1-3 describe the preparation of difunctional methacrylate-terminated polyester oligomers. The midblock is PLGA-PCL-PLGA with a molecular weight of 6 kilodaltons and PCL is 40 wt.% of the total molecular weight (MW). The PLGA is a random copolymer of lactide (L) and glycolide (G) with a L:G weight ratio of 1:1.

[0424] The molar ratio and mass of each reagent used to synthesize a 1 kg batch of HO-PLGA-b-PCL-b-PLGA-OH as discussed in Examples 1 and 2 are provided in Table 3 below.

[0425] Table 3: Mole ratio and mass of reagents for Example 1 and Example 2

[0426]

[0427] Example 1: HO-PCL-OH synthesis

[0428] A round bottom flask was dried in a drying cabinet overnight and cooled to room temperature under N2flow. Caprylate and stannous octoate were added to the round bottom flask via a glass syringe and syringe needle. The reaction flask contents were heated to 130 °C. At the same time, diethylene glycol was heated to 130 °C. After preheating, diethylene glycol was added to the reaction flask as an initiator and the reaction was allowed to proceed until complete monomer conversion. H 1 NMR was used to monitor monomer conversion. Once complete monomer conversion was reached, the reaction was stopped and the reaction contents were cooled to room temperature. HO-PCL-OH was precipitated from chloroform into cold MeOH to obtain a white solid.H 1 NMR, DSC, FTIR, and THF GPC were used to characterize HO-PCL-OH.

[0429] Example 2: HO-PLGA-b-PCL-b-PLGA-OH synthesis

[0430] HO-PCL-OH prepared in Example 1 and different amounts of D,L-lactide and glycolide were added to a round bottom flask under N2and heated to 140 °C to melt the reaction contents. After melting, the temperature was reduced to 120 °C and stannous caprylate was added. The reaction was continued with stirring while monitoring monomer conversion with H 1 NMR and THF GPC. Once the reaction reached the desired molecular weight, the reaction contents were cooled to room temperature, dissolved in chloroform, and precipitated in cold diethyl ether three times. The precipitate was dried under vacuum.

[0431] Example 3: MA-PLGA-b-PCL-b-PLGA-MA synthesis

[0432] The molar ratio and mass of each reagent used to synthesize a 1 kg batch of MA-PLGA-b-PCL-b-PLGA-MA are provided in Table 4 below.

[0433] Table 4: Mole ratio and mass of each reagent for Example 3

[0434]

[0435] The HO-PLGA-b-PCL-b-PLGA-OH prepared in Example 2 was dissolved in anhydrous DCM in a round bottom flask under N2. Triethylamine and BHT were added to the reaction flask and the reaction flask was cooled to 0 °C in an ice water bath. The reaction flask was equipped with a pressure equalizing addition funnel, which was charged with methacryloyl chloride. Once the reaction flask reached 0 °C, the methacryloyl chloride was added dropwise over 2 hours. The reaction was carried out at 0 °C for 12 hours and then at room temperature for 24 hours. Once the reaction was complete, the reaction contents were washed with distilled water 2 times to remove triethylamine hydrochloride, washed with saturated Na2C03, and then dried over magnesium sulfate. The DCM layer was collected and dried using rotary evaporation. The final product was characterized using THF GPC, H 1 NMR, FTIR, and DSC.

[0436] Example 4-6: Preparation of three-armed MA terminated polyester oligomers

[0437] Examples 4-6 describe the preparation of a tri-armed or star-shaped bioabsorbable polyester oligomer. Each arm is capped with a methacrylate ester. Each arm has a molecular weight of 2 kilodaltons and is a block copolymer of random poly(lactide-co-glycolide) (PLGA) segments and poly(caprolactone) (PCL) segments, with PCL being the core of the oligomer. PCL comprises 40 wt.% of the total molecular weight (MW). The PLGA is a random copolymer of lactide (L) and glycolide (G) with a L:G weight ratio of 1 : 1.

[0438] Example 4: PCL-3oh synthesis

[0439] The molar ratios and masses of each reagent used to synthesize a 1 kg batch of (PLGA-b-PCL)-3OH as discussed in Examples 4 and 5 are provided in Table 5 below.

[0440] Table 5: Examples of mole ratio and mass of each reagent for Example 4 and Example 5

[0441]

[0442] A round bottom flask was dried in a drying cabinet overnight and cooled to room temperature under a stream of N2. Caprolactone and stannous octoate were added to the round bottom flask via a glass syringe and syringe needle. The reaction flask contents were heated to 130 °C. Simultaneously, trimethylolpropane (TMP) was heated to 130 °C. Once preheated, the TMP was added to the reaction flask as an initiator and the reaction was allowed to proceed until complete monomer conversion. The final product was characterized using THF GPC, H 1NMR was used to monitor monomer conversion. Once full monomer conversion was achieved, the reaction was stopped and the reaction contents were cooled to room temperature. (PCL)-3OH was precipitated from chloroform into cold MeOH to obtain a white solid. H1 NMR, DSC, FTIR, and GPC were used to characterize (PCL)-3OH.

[0443] Example 5: (PCL-b-PLGA)-3OH synthesis

[0444] (PCL)-3OH prepared in Example 4 and different amounts of D,L-lactide and glycolide were added to a round bottom flask under N2and heated to 140 °C to melt the reaction contents. After melting, the temperature was reduced to 120 °C and stannous octoate was added. The reaction was continued with stirring while monitoring the monomer conversion with H 1 NMR and THF GPC were used to monitor monomer conversion. Once the reaction reached the desired molecular weight, the reaction contents were cooled to room temperature, dissolved in chloroform, and precipitated in cold diethyl ether three times. The precipitate was dried under vacuum.

[0445] Example 6: (PCL-b-PLGA)-3MA synthesis

[0446] The molar ratio and mass of each reagent used to synthesize 1 kg batch of (PLGA-b-PCL)-3MA are provided in Table 6 below.

[0447] Table 6: Mole ratio and mass of each reagent for Example 6

[0448]

[0449] (PCL-b-PLGA)-3OH prepared in Example 5 was dissolved in anhydrous DCM in a round bottom flask under N2. Triethylamine (TEA) and BHT were added to the reaction flask and the reaction flask was cooled to 0 °C in an ice water bath. The reaction flask was equipped with a pressure-equalizing addition funnel, which was charged with methacryloyl chloride. Once the reaction flask reached 0 °C, the methacryloyl chloride was added dropwise over 2 hours. The reaction was carried out at 0 °C for 12 hours and then at room temperature for 24 hours. After the reaction was complete, the precipitate was removed by vacuum filtration. The filtrate was collected and the DCM was removed with rotary evaporation. The resulting viscous oil was dissolved in THF and precipitated into cold methanol. The precipitate was dissolved in DCM and washed with aqueous HC1 (3%, 2 times), saturated aqueous sodium bicarbonate, and saturated aqueous sodium chloride, then dried over magnesium sulfate. The magnesium sulfate was filtered by vacuum filtration and the filtrate was collected. The DCM was removed by rotary evaporation and the solid product was collected and characterized with GPC, H 1 NMR, FTIR, and DSC were used to characterize the solid product.

[0450] Example 7: Difunctional oligomer resin formulation

[0451] The following components were mixed together in the following weight percentages (wt% of resin) to provide an exemplary resin for additive manufacturing:

[0452] (1) 66.2% of the difunctional oligomer prepared as in Examples 1-3 above;

[0453] (2) 3.5% trimethylolpropane trimethacrylate (TMPTMA) reactive diluent;

[0454] (3) 28.4% N-methyl pyrrolidone (NMP) non-reactive diluent; and

[0455] (4) 1.89% of 819 photoinitiator.

[0456] Example 8: Three-armed oligomer resin formulation

[0457] The following components were mixed together in the following weight percentages (wt% of resin) to provide an exemplary resin for additive manufacturing:

[0458] (1) 68.6% of the tri-arm oligomer prepared as in Examples 4-6 above;

[0459] (2) 29.4% N-methyl pyrrolidone (NMP) non-reactive diluent; and

[0460] (3) 1.96% of 819 photoinitiator.

[0461] Example 9: Additive manufacturing and post-processing

[0462] Five exemplary adjuncts were prepared. The first exemplary adjunct (Adjunct 1) was structurally similar to the Adjunct 800 in FIGS. 8A-8F except that the first adjunct was formed from two longitudinal rows of 20 unit cells. Four other exemplary adjuncts were structurally similar to the Adjunct 3100 (Adjunct 2) shown in FIGS. 31A-31D , the Adjunct 3200 (Adjunct 3) shown in FIGS. 32A-32D , the Adjunct 3300 (Adjunct 4) shown in FIGS. 33A-33E , and the Adjunct 3400 (Adjunct 5) shown in FIGS. 34A-34E , respectively. The five adjuncts were prepared by additive manufacturing according to standard techniques on a Carbon Inc. M1 or M2 device available from Carbon Inc., 1089 Mills Way, Redwood City, California (zip code: 94063). The resin formulation for each adjunct is provided in Table 7 below.

[0463] Table 7: Exemplary attachment resin formulations

[0464]

[0465] When the resin contains a non-reactive diluent, the object may experience overall shrinkage to the extent of the non-reactive diluent loading during washing / extraction. Therefore, a size scaling factor is applied to the part stereolithography (.stl) file or 3D manufacturing format (3MF) file to enlarge the printed appendages and intentionally account for subsequent shrinkage during post-processing steps.

[0466] Post-treatment of each appendage is performed as follows: After removing the build platform from the equipment, wipe off excess resin from a flat surface around the appendage, leaving the platform on its sides to drain for approximately 10 minutes. Carefully remove the appendage from the platform. Wash the appendage three times in acetone, each time for 30 seconds at 280 rpm on a track-type shaker, followed by drying for 5 minutes between washes. After the third wash, allow the appendage to dry for 30 minutes, then proceed with PrimeCure. TM In the UV overflow curing equipment, each side is cured for 20 seconds.

[0467] Next, residual non-reactive diluents (e.g., N-methylpyrrolidone or propylene carbonate) were extracted from the appendix by immersing it in acetone and agitating it on an orbital oscillator at room temperature for approximately 18 hours, with the solvent being replaced every 12 hours. The appendix was then removed from the acetone and vacuum-dried overnight at 60°C. Residual solvent in the appendix was then examined using extraction methods for GCMS and FTIR. If no residual solvent was detected, the viscosity of the portion was checked. If the appendix remained viscous, it was flood-cured under nitrogen in an LED-based floodlight (e.g., a PCU LED N2 floodlight, available from Dreve Group of Unna, Germany).

[0468] Example 10: Stress-strain analysis of representative samples

[0469] FIG. 56 The stress-strain curves for accessory 1 of Example 9 are shown, and FIG. 57 The stress-strain curves for appendices 2 to 5 of Example 9 are shown.

[0470] FIG. 56 and FIG. 57The stress-strain curves shown are generated by placing the appendage between a pair of 25 mm diameter circular stainless steel compression plates (available from TA Instruments, 159 Lukens Drive, New Castle, Delaware 19720 USA) on an RSA-G2 solids analyzer. The plates are lowered at a rate of 0.1 mm per step until the initial axial force reaches between 0.03 N and 0.05 N. The plate is then equilibrated at 37°C for 120 seconds, followed by a compression test (lowering the plates at 10 mm / min for 14 seconds until a gap height of 0.7 mm or an overload force of approximately 17 N is reached, whichever occurs first, while recording the real-time compressive stress). This process produces the stress-strain curve for each appendage. Therefore, the stress-strain curves are generated by compressing each appendage from its corresponding uncompressed height of 3 mm (within manufacturing tolerances) to its corresponding compressed height. Table 8 below provides the compressed height and strain of each appendage under applied stress. These measurements are based on actual manufactured accessories (including any measurement errors of the measurement system, such as a deviation of 50 μm to the uncompressed height and / or manufacturing tolerances, such as a deviation of 100 μm to the uncompressed height).

[0471] Table 8. Compression height and strain measurements for Attachment 1-5

[0472] Measurement conditions Compression height (mm) Strain Attachment 1 Applied stress of 90 kPa 0.81 73 Attachment 2 Applied stress of 30 kPa 1.53 49 Attachment 3 Applied stress of 9.43 kPa 1.2 60 Attachment 4 Applied stress of 30 kPa 1.5 50 Attachment 5 Applied stress of 30 kPa 1.35 55

[0473] like FIG. 56 As shown, appendages are formed by cells based on non-stretcher elements, for example... FIGS. 8A-8F The appendage 800 described herein indicates that: (i) the cell structure is sufficiently stable such that even with a wall thickness of approximately 0.2 mm, the structure can be successfully printed and post-processed as described above; (ii) the appendage undergoes extensive buckling deformation and achieves a stress plateau between approximately 0.1 strain (approximately 10% deformation) and approximately 0.73 strain (73% deformation); and (iii) the appendage has bistable properties, thus the cell structure is deformable and achieves a new stable form that does not change until an additional force is applied, potentially providing the surgeon with tactile feedback on the deformable state of the appendage.

[0474] like FIG. 57 As shown, an appendage formed by strut-based strut cells, for example FIGS. 31A-31D 3100, an accessory FIGS. 32A-32D 3200, an accessory FIGS. 33A-33E The appendages 3300 and FIGS. 34A-34EThe appendages exhibit a stress "plateau" between 5 kPa and 20 kPa within a strain range of 10% to 60%. This result is at least in part based on the structural configuration of the cells. Specifically, each cell is designed such that the spacer struts (e.g., struts of the internal structure) fold inward without contacting each other during compression of the appendages. Thus, densification of the appendages (e.g., reaching a solid height) can be delayed (e.g., occurring at higher strains).

[0475] Example 11: Stress-strain analysis of representative samples

[0476] Six exemplary appendages were prepared in a manner similar to that described in Example 9, referred to herein as Sample 1, Sample 2, Sample 3, Sample 4, Sample 5, and Sample 6, except that the resin formulation for each of Samples 1 to 6 was: a trifunctional oligomer (methacrylate end groups) having a PCL middle block and a PLGA end block (85:15 L:G weight ratio); with a target molecular weight of 6,000 Daltons. Sample 1 was formed from cells of a repeating interconnected Schwarz-P structure, and Samples 2 to 5 were formed from corresponding repeating interconnected modified Schwarz-P structures, wherein the top and / or bottom of the initial Schwarz-P structure were trimmed. Therefore, the geometric properties of the repeating cells for each sample were different. A list of geometric cell properties for each appendage based on ideal / expected dimensions is provided in Table 9 below.

[0477] Table 9. Exemplary cell geometry properties

[0478]

[0479] *use FIGS. 9A-9B Using cell 810 as a reference, the height extends in the x direction, the width extends in the y direction, and the length extends in the z direction.

[0480] The total height reflects the uncompressed (untrimmed) cell height of Sample 1 and the uncompressed but trimmed heights of Samples 2 through 6.

[0481] The stress-strain curves for samples 1 to 6 were generated in a manner similar to that described in Example 10, and... FIG. 58These curves are shown in FIG. 6. As shown, each cell was formed from the same resin, but each sample had a different stress-strain curve. Thus, these different stress-strain curves show the relationship between the geometric characteristics of the cell (e.g., height, width, length, and wall thickness) and the resulting appendage’s stress-strain response when compressed from the corresponding uncompressed height (listed as total height in Table 9 above) to the corresponding compressed height. Thus, in addition to the constituent components of the cell, its various geometric characteristics need to be considered and, thus, tailored to achieve an appendage with a desired stress-strain response, such as the stress-strain responses described herein. The compressed height and strain of each sample at an applied stress of 90 kPa are provided in Table 10 below. These measurements are based on the actually manufactured appendages (including any measurement error of the measurement system, e.g., 50 pm deviation from uncompressed height and / or manufacturing tolerances, e.g., 100 pm deviation from uncompressed height).

[0482] Table 10. Compression height and strain measurements for samples 1-6 at 90 kPa

[0483]

[0484] Examples 12-14: Preparation of tri-arm MA-terminated polyester oligomers

[0485] Examples 12-14 describe the preparation of a three-arm or star-shaped bioabsorbable polyester oligomer. Each arm is terminated with a methacrylate ester. The molecular weight of each arm is 2 kilodaltons and is a block copolymer of poly(L-lactic acid) (PLLA) and poly(caprolactone-r-L-lactic acid) (PCLLA), where PCLLA is the core of the oligomer. PCLLA comprises 70 w.t% of the total molecular weight (MW), and the CL:L ratio is 60:40.

[0486] The molar ratios and masses of each reagent used to synthesize 1 kg batches of (PLLA-b-PCLLA)-3OH as discussed in Example 12 and Example 13 are provided in Table 11 below.

[0487] Table 11: Exemplary molar ratios and masses of each reagent for Examples 12 and 13

[0488]

[0489] Example 12: PCLLA-3OH synthesis

[0490] A round bottom flask was dried overnight in a drying cabinet and cooled to room temperature under a stream of N2. Caprolactone, L-lactide, and stannous octoate were added to the round bottom flask. The reaction flask contents were heated to 130 °C. Simultaneously, trimethylolpropane (TMP) was heated to 130 °C. After preheating, the TMP was added to the reaction flask as an initiator and the reaction was allowed to proceed until the monomers were fully converted. H 1NMR monitored monomer conversion. Once full monomer conversion was reached, the reaction was stopped and the reaction contents were cooled to room temperature. (PCLLA)-3OH was precipitated from chloroform into cold MeOH to obtain a white solid. H 1 NMR, DSC, FTIR, and THF GPC were used to characterize (PCLLA)-3OH.

[0491] Example 13: (PLLA-b-PCLLA)-3OH synthesis

[0492] (PCLLA)-3OH and L-lactide prepared in Example 12 were added to a round bottom flask under N2and heated to 140 °C to melt the reaction contents. Once melted, the temperature was lowered to 120 °C and stannous octoate was added. The reaction was continued with stirring while the reaction was monitored by H 1 NMR and THF GPC monitored monomer conversion. Once the reaction reached the desired molecular weight, the reaction contents were cooled to room temperature, dissolved in chloroform, and precipitated in cold diethyl ether three times. The precipitate was dried under vacuum.

[0493] Example 14: (PLLA-b-PCLLA)-3MA synthesis

[0494] The molar ratio and mass of each reagent used to synthesize 1 kg batch of (PLLA-b-PCLLA)-3MA is provided in Table 12 below.

[0495] Table 12: Exemplary molar ratios and masses of each reagent for Example 14

[0496]

[0497] (PCLLA)-3OH prepared in Example 13 was dissolved in anhydrous DCM in a round bottom flask under N2. Triethylamine (TEA) and 400 ppm of BHT were added to the reaction flask and the reaction flask was cooled to 0 °C in an ice water bath. The reaction flask was equipped with a pressure-equalizing addition funnel, which was charged with methacryloyl chloride. Once the reaction flask reached 0 °C, the methacryloyl chloride was added dropwise over 2 hours. The reaction was carried out at 0 °C for 12 hours and then at room temperature for 24 hours. After the reaction was complete, the precipitate was removed by vacuum filtration. The filtrate was collected and the DCM was removed with rotary evaporation. The resulting viscous oil was dissolved in THF and precipitated into cold methanol. The precipitate was dissolved in DCM and washed with aqueous HCL (3%, 2 times), saturated aqueous sodium bicarbonate, and saturated aqueous sodium chloride, then dried over magnesium sulfate. The magnesium sulfate was filtered by vacuum filtration and the filtrate was collected. The DCM was removed by rotary evaporation and the solid product was collected and characterized by THF GPC, H 1 The solid product was characterized by NMR, FTIR, and DSC.

[0498] Example 15: Bi-functional oligomer resin formulation

[0499] The following components were mixed together in the following weight percentages (wt% of resin) to provide an exemplary photopolymerizable resin for additive manufacturing:

[0500] (1) 58.82% of the difunctional oligomer as prepared in Example 12-13 above;

[0501] (2) 39.22% propylene carbonate (PC) non-reactive diluent; and

[0502] (3) 1.96% of 819 photoinitiator.

[0503] The instruments disclosed herein can be designed to be disposed of after a single use, or they can be designed to be used multiple times. Regardless, of the number of times they can be used, the instruments can be reconditioned for reuse after at least one use. Reconditioning can include any combination of the steps of disassembly of the instrument, followed by cleaning and replacement or refurbishment of any of the various parts, members or components of the instrument, and subsequent reassembly. In particular, the instruments can be disassembled, and any number of the particular pieces or parts of the instrument can be selectively replaced or removed in any combination. Upon cleaning and / or replacement of particular parts, the instrument can be reassembled for subsequent use either at a reconditioning facility, or by a surgical team immediately prior to a surgical procedure. Those skilled in the art will appreciate that reconditioning of an instrument can utilize a variety of techniques for disassembly, cleaning / replacement, and reassembly. Use of such techniques, and the resulting reconditioned instrument, are all within the scope of the present application.

[0504] Further, in the present disclosure, like-named components of the embodiments can be described with like reference numerals throughout the several embodiments. Unless otherwise specified, a "first" component of an embodiment could be the same as a "second" component of another embodiment. Furthermore, in the description of the disclosed systems, devices, and methods, any linear or circular dimensions can be easily determined by one of ordinary skill in the art based on the illustrations of the drawin...

Claims

1. A stapling assembly for use with a surgical stapler, comprising: a cartridge having a plurality of staples disposed therein configured to be deployed into tissue; and a non-fibrous adjunct formed from at least one fused bioabsorbable polymer and configured to be releasably retained on the cartridge such that the adjunct can be attached to tissue by the plurality of staples in the cartridge, the adjunct having a first end, a second end, and a longitudinal axis extending between the first end and the second end, wherein the adjunct comprises at least two different compression zones, each compression zone defined by a different lattice structure of repeating geometric cells formed from interconnected struts, and wherein each lattice structure has a different compression strength such that the adjunct has a variable compression strength along a transverse direction relative to its longitudinal axis; wherein the at least two different compression zones include a first compression zone having a first compression strength and a second compression zone having a second compression strength that is less than the first compression strength; wherein the cartridge includes a slot extending into and along at least a portion of the cartridge and configured to receive a cutting element, and wherein the second compression zone is configured to at least partially overlap the slot when the adjunct is attached to the cartridge.

2. The stapling assembly of claim 1, wherein, At least a portion of the first compression zone is positioned around a perimeter of the adjunct.

3. The stapling assembly of claim 1, wherein, The at least two different compression zones include a third compression zone having a third compression strength that is less than the second compression strength.

4. The stapling assembly of claim 3, wherein, At least a portion of the third compression zone is positioned around a perimeter of the adjunct.

5. The stapling assembly of claim 3, wherein, The cartridge includes a slot extending into and along at least a portion of the cartridge and configured to receive a cutting element, and wherein the third compression zone is configured to at least partially align with the slot when the adjunct is attached to the cartridge.

6. The stapling assembly of claim 1, wherein, The adjunct has a tissue-contacting surface and a cartridge-contacting surface opposite the tissue-contacting surface, the cartridge-contacting surface having a plurality of attachment features extending outwardly therefrom and configured to extend into a recess defined within the cartridge.

7. The stapling assembly of claim 6, wherein, The plurality of attachment features are arranged in a repeating pattern across the cartridge-contacting surface, the repeating pattern configured to substantially overlap a repeating pattern of the recess defined within the cartridge.

8. A stapling assembly for use with a surgical stapler, comprising: a cartridge having a plurality of staples disposed therein configured to be deployed into tissue; and a non-fibrous adjunct formed from at least one fused bioabsorbable polymer and configured to be releasably retained on the cartridge such that the adjunct can be attached to tissue by the plurality of staples in the cartridge, the adjunct comprising: a first compression zone having a first compression strength, the first compression zone defined by a first lattice structure formed of a plurality of first repeating unit cells, wherein the first repeating unit cells are first triply periodic minimal surface structures, and a second compression zone having a second compression strength different from the first compression strength, the second compression zone defined by a second lattice structure formed of a plurality of second repeating unit cells different from the first repeating unit cells, wherein the second repeating unit cells are second triply periodic minimal surface structures; wherein the first compression zone and the second compression zone are positioned adjacent to each other and laterally offset from each other relative to a longitudinal axis of the adjunct.

9. The stapling assembly of claim 8, wherein, the first triply periodic minimal surface structures vary in at least one of height and wall thickness compared to the height and wall thickness of the second triply periodic minimal surface structures.

10. The stapling assembly of claim 8, wherein, the adjunct comprises a third compression zone having a third compression strength different from the first compression strength and the second compression strength, the third compression zone defined by a third lattice structure formed of a plurality of third repeating unit cells, and wherein the third compression zone is laterally offset from the first compression zone and the second compression zone.

11. The stapling assembly of claim 10, wherein, the third repeating unit cells are third triply periodic minimal surface structures.

12. The stapling assembly of claim 11, wherein, the first triply periodic minimal surface structures, the second triply periodic minimal surface structures, and the third triply periodic minimal surface structures vary in at least one of height and wall thickness relative to each other.

13. The stapling assembly of claim 11, wherein, the first triply periodic minimal surface structures, the second triply periodic minimal surface structures, and the third triply periodic minimal surface structures are Schwarz-P structures.

14. The stapling assembly of claim 10, wherein, the first compression zone is an innermost compression zone of the adjunct, and the third compression zone is an outermost compression zone of the adjunct.

15. The stapling assembly of claim 14, wherein, the third compression strength is less than the first compression strength and the second compression strength.

16. The stapling assembly of claim 15, wherein, the cartridge comprises a slot extending into and along at least a portion of the cartridge and configured to receive a cutting element, and wherein the first compression zone is a proximal-most compression zone relative to the slot.

17. A stapling assembly for use with a surgical stapler, comprising: a cartridge having a plurality of staples disposed therein configured to be deployed into tissue; and a non-fibrous adjunct formed of at least one fused bioabsorbable polymer and configured to be releasably retained on the cartridge such that the adjunct can be attached to tissue by the plurality of staples in the cartridge, the adjunct having a first end, a second end, and a longitudinal axis extending between the first end and the second end, wherein the adjunct comprises at least two different compression zones, each compression zone defined by a different lattice structure of repeating geometric cells formed of interconnected struts, and wherein each lattice structure has a different compression strength such that the adjunct has a variable compression strength along a lateral direction relative to its longitudinal axis; wherein the at least two different compression zones include a first compression zone having a first compression strength and a second compression zone having a second compression strength that is less than the first compression strength, and a third compression zone having a third compression strength that is less than the second compression strength; wherein the cartridge includes a slot extending into and along at least a portion of the cartridge and configured to receive a cutting element, and wherein the third compression zone is configured to at least partially align with the slot when the adjunct is attached to the cartridge.

18. The stapling assembly of claim 17, wherein, At least a portion of the first compression zone is positioned around a perimeter of the adjunct.

19. The stapling assembly of claim 17, wherein, At least a portion of the third compression zone is positioned around a perimeter of the adjunct.

20. The stapling assembly of claim 17, wherein, The adjunct has a tissue-contacting surface and a cartridge-contacting surface opposite the tissue-contacting surface, the cartridge-contacting surface having a plurality of attachment features extending outwardly therefrom and configured to extend into a recess defined within the cartridge.

21. The stapling assembly of claim 20, wherein, The plurality of attachment features are arranged in a repeating pattern across the cartridge-contacting surface, the repeating pattern configured to substantially overlap a repeating pattern of the recess defined within the cartridge.

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