System and method for regulating the absorption pathway in bioabsorbable materials

Abstract

The disclosed technology includes a bioabsorbable material configured to be delivered to tissue. The material includes a porous body comprising at least one polymer having a first zone having a first crosslinking density and a second zone having a second crosslinking density different from that of the first zone. The first and second zones form a compressive strength gradient along a portion of the porous body.

Description

[Technical Field]

[0001] (Cross-reference of related applications) This application claims priority to U.S. Provisional Patent Application No. 63 / 522,660, filed on 22 June 2023, and U.S. Non-Provisional Patent Application No. 18 / 485,083, filed on 11 October 2023, under Section 119 of the U.S. Patent Act, the entire contents of which are incorporated herein by reference in full.

[0002] (Field of Invention) The present invention generally relates to systems and methods for modifying absorption pathways in bioabsorbable materials via chemical skeletons and / or coatings. [Background technology]

[0003] Surgical staplers are used in surgical procedures to close openings in tissues, blood vessels, tubes, shunts, or other objects or body parts related to a particular procedure. Openings may be naturally occurring, such as passages within blood vessels or viscera like the stomach, or they may be created by a surgeon during a surgical procedure, such as by forming a bypass or anastomosis through tissue or blood vessel puncture, or by incising tissue during stapling.

[0004] Most staplers have a handle (some of which are directly user-operable, others via a robotic interface), a slender shaft extending from the handle, and a pair of movable opposing jaws formed at its end, which are used to hold and shape staples between them. Staples are typically housed in a staple cartridge, which can hold multiple rows of staples and is often positioned within one of the two jaws for releasing staples to the surgical site. During use, the jaws are positioned so that the object to be stapled is placed between them, and when the jaws are closed and the device is activated, the staples are released and shaped. Some staplers include a knife configured to move between rows of staples in the staple cartridge and, between the stapled rows, longitudinally incise and / or open the stapled tissue. [Overview of the Initiative] [Means for solving the problem]

[0005] According to one embodiment of the present invention, a bioabsorbable material configured to be delivered to tissue is provided. The material may include a first polymerizable compound and a second polymerizable compound. The first polymerizable compound may include a reaction product of a polyol and an isocyanate and may be configured to degrade according to a first degradation profile. The second polymerizable compound may be configured to degrade according to a second degradation profile different from the first degradation profile. The material may undergo a phase transition in response to exposure to a fluid having at least one of a predetermined temperature, an enzyme-catalyst, and a predetermined pH.

[0006] According to one embodiment of the present invention, a bioabsorbable material configured to be delivered to tissue is provided. The material may include a copolymer skeleton. The copolymer skeleton may include a first polymerizable compound and a second polymerizable compound. The first polymerizable compound may include a reaction product of a polyol and an isocyanate and may be configured to degrade according to a first degradation profile. The second polymerizable compound may be configured to degrade according to a second degradation profile different from the first degradation profile. The material may undergo a phase transition in response to exposure to a fluid having a predetermined temperature.

[0007] According to one embodiment of the present invention, a bioabsorbable material configured to be delivered to tissue is provided. The material may include a first polymerizable compound and a second polymerizable compound. The first polymerizable compound may include a reaction product of a polyol and an isocyanate and may be configured to decompose according to a first degradation profile. The second polymerizable compound may coat the first polymerizable compound, and as a result the coating may prevent the first polymerizable compound from being exposed to fluid ingress over a predetermined period of time. The material may undergo a phase transition in response to exposure to a fluid having a predetermined pH. [Brief explanation of the drawing]

[0008] The present invention will be more fully understood by reading the following embodiments in conjunction with the accompanying drawings. [Figure 1] This is a perspective view of an exemplary embodiment of a conventional surgical staple fastening and cutting instrument. [Figure 2A] Figure 1 is a top view of a staple cartridge for use with surgical staple fastening and cutting instruments. [Figure 2B] Figure 2A is a side view of the staple cartridge. [Figure 3] Figure 2A is a side view of a staple in its unfired (pre-implantation) configuration, which may be placed within the staple cartridge of the surgical cartridge assembly. [Figure 4] Figure 1 is a perspective view of the knife and launching bar ("E-shaped beam section") of the surgical staple fastening and cutting instrument. [Figure 5] Figure 1 is a perspective view of the wedge thread of the staple cartridge for a surgical staple fastening and cutting instrument. [Figure 6A] This is a longitudinal cross-sectional view of an exemplary surgical cartridge assembly having a compressible, non-fibrous auxiliary material attached to the top or deck surface of a staple cartridge. [Figure 6B] This is a longitudinal cross-sectional view of a surgical end effector having an anvil pivotably connected to an elongated channel, and a surgical cartridge assembly (Figure 6A) disposed within and connected to the elongated channel, showing the anvil in a closed position with no tissue between it and the auxiliary material. [Figure 7] Figure 7A is a schematic partial view showing the auxiliary material shown in Figures 6A and 6B when implanted in tissue. Figure 7B is a magnified view of an exemplary auxiliary material having a porous structure. [Figure 8] This is a perspective view of an exemplary cartridge assembly. [Figure 9A] This is a side view of an exemplary end effector having an auxiliary material for bioabsorbable material in a delivery configuration. [Figure 9B] This is a side view of an exemplary end effector having an auxiliary material of bioabsorbable material after firing and release from the cartridge. [Figure 10A] This is an overhead perspective view of an example of an auxiliary material after use. [Figure 10B] This is a side view of an example of an auxiliary material after use. [Figure 11] This flowchart illustrates an exemplary method for forming surgical aids using a controllable absorption pathway for bioabsorbable materials. [Figure 12] This flowchart illustrates an exemplary method for forming surgical aids using a controllable absorption pathway for bioabsorbable materials. [Modes for carrying out the invention]

[0009] The following detailed description should be read with reference to the drawings, and like elements in different drawings are numbered the same. The drawings are not necessarily to scale and depict selected embodiments and are not intended to limit the scope of the invention. The embodiments for carrying out the invention are illustrative and not restrictive, and are given by way of example for illustrating the principles of the invention. This specification enables those skilled in the art to make and use the invention and describes some embodiments, adaptations, variations, alternatives, and usage examples of the invention, including what is currently considered to be the best mode for carrying out the invention.

[0010] As used herein, the term "about" or "substantially" with respect to any numerical value or range indicates a suitable dimensional tolerance that enables a part or collection of components to function for the intended purpose described herein. More specifically, "about" or "substantially" can refer to a range of values within ±10% of the recited value. For example, "about 90%" can refer to a range of values from 81% to 99%.

[0011] As used herein, "degradation" refers to the process of degradation of polymer chains for absorption into the surroundings (e.g., tissue, cells, fluid, etc.) as atoms, molecules, or ions. Degradation includes cleavage of primary and secondary bonds via thermal degradation, photodegradation, catalytic or enzymatic degradation, oxidative degradation, ionic degradation, and biodegradation.

[0012] The term "polymerizable compound" means a compound containing one or more polymerizable groups. This term encompasses, for example, monomers, macromers, oligomers, prepolymers, crosslinking agents, and the like.

[0013] As used herein, “polymerizable group” is a group capable of undergoing chain growth polymerization, such as a carbon-carbon double bond, which can polymerize when subjected to free radical and / or cationic polymerization, for example, when subjected to conditions that initiate radical polymerization. Non-limiting examples of free radical polymerizable groups include (meth)acrylates, styrenes, vinyl ethers, (meth)acrylamides, N-vinyl lactams, N-vinylamides, O-vinylcarbamates, O-vinyl carbonates, and other vinyl groups. Preferably, free radical polymerizable groups include (meth)acrylates, (meth)acrylamides, N-vinyl lactams, N-vinylamides, polyester polyols, poloxamers, and styryl functional groups, as well as any mixtures thereof. Preferably, free radical polymerizable groups include (meth)acrylates, (meth)acrylamides, polyester polyols, poloxamers, and mixtures thereof. Polymerizable groups may be unsubstituted or substituted. For example, the nitrogen atom in (meth)acrylamide may be bonded to hydrogen, or the hydrogen may be substituted by an alkyl or cycloalkyl group (which may itself be further substituted).

[0014] As used herein, the term “polyurethane” refers to the polymer reaction product of an isocyanate and a polyol, and is not limited to polymers containing only urethane bonds or polyurethane bonds. It will be well understood by those skilled in the art to prepare polyurethanes that polyurethane polymers may also contain bonds such as allophanates, carbodiimides, and other bonds described herein, in addition to urethane bonds.

[0015] Any type of free radical polymerization, including bulk, solution, suspension, and emulsion, as well as any controlled radical polymerization method, such as stable free radical polymerization, nitrogen oxide-mediated living polymerization, atom transfer radical polymerization, reversible addition-cleavage chain transfer polymerization, and organotellurium-mediated living radical polymerization, may be used.

[0016] The terms “reaction system,” “reactive formulation,” “reaction product,” and “reactive mixture” are used interchangeably herein and all refer to combinations of reactive compounds used to produce the bioabsorbable materials according to this disclosure.

[0017] The term "room temperature" refers to a temperature of approximately 20°C, which means a temperature range of 18°C ​​to 25°C. Such temperatures include 18°C, 19°C, 20°C, 21°C, 22°C, 23°C, 24°C, and 25°C.

[0018] Unless otherwise specified, the "weight percentage" (indicated as %wt. or wt.%) of a component in a composition refers to the weight of the component relative to the total weight of the composition in which it is present, and is expressed as a percentage.

[0019] The terms "glass transition temperature" and "T" as used herein refer to. g This refers to the temperature at which a reversible transition occurs from a hard glassy state to a rubbery elastic state.

[0020] Surgical staple fastening assemblies, as well as methods for manufacturing and using the same, are provided. Generally, a surgical staple fastening assembly may include a staple cartridge in which staples are disposed internally, and an auxiliary material configured to be releasably held on the staple cartridge. As discussed herein, the various auxiliary materials provided may be configured to compensate for changes in tissue properties, such as changes in tissue thickness, and / or to promote tissue endoplasticity when the auxiliary material is stapled to the tissue. As discussed herein, the auxiliary material may include bioabsorbable materials such as foams.

[0021] An exemplary staple fastening assembly, as described herein and shown in the drawings, may include various features to facilitate the application of surgical staples. However, it will be understood by those skilled in the art that a staple fastening assembly may include only some of these features, and / or may include various other features known in the art. The staple fastening assemblies described herein are intended to represent specific exemplary embodiments only. Furthermore, although auxiliary materials are described in relation to surgical staple cartridge assemblies, auxiliary materials may be used in relation to the reloading of staples in non-cartridge-based surgical instruments or any type of surgical instrument.

[0022] Figure 1 shows an exemplary surgical stapling and cutting device 100 suitable for use with implantable auxiliary materials. The illustrated surgical stapling and cutting device 100 includes an end effector 106 having an anvil 102 pivotally connected to an elongated channel 104. As a result, the end effector 106 can move between an open position, as shown in Figure 1, and a closed position in which the anvil 102 is positioned adjacent to the elongated channel 104 and engages tissue between them. The end effector 106 can be attached at its proximal end to an elongated shaft 108 that forms an implement 110. When the end effector 106 is closed, or at least substantially closed (for example, when the anvil 102 moves from the open position in Figure 1 toward the elongated channel), the implement 110 can present a cross section small enough to be suitable for inserting the end effector 106 through a trocar. Device 100 is configured to staple and cut tissue, but surgical devices configured to staple tissue but not cut it are also contemplated herein.

[0023] In various situations, the end effector 106 can be operated by a handle 112 connected to the elongated shaft 108. The handle 112 includes a user control unit such as a rotary knob 114 that rotates the elongated shaft 108 and the end effector 106 around the longitudinal axis (Ls) of the elongated shaft 108, and an articulated axis (T) which is substantially transverse to the longitudinal axis (Ls) of the elongated shaft 108. A The system may include an articulation control unit 115 that can articulate the end effector 106 around the pistol grip 118. Further control units may include a closing trigger 116 that can pivot relative to the pistol grip 118 to close the end effector 106. For example, when the closing trigger 116 is clamped, a closing release button 120 may be provided on the outside of the handle 112, so that pressing the closing release button 120 releases the clamp on the closing trigger 116 and opens the end effector 106. The handle 112 may also take the form of an interface for connection to a surgical robot.

[0024] In some embodiments, the firing trigger 122 can pivot relative to the closing trigger 116, thereby allowing the end effector 106 to simultaneously cut and staple the tissue clamped inside it. The firing trigger 122 may be powered, require user force to engage, or be a combination of both. A manual firing release lever 126 allows the firing system to be retracted if necessary before it completes its movement for firing, and further allows a surgeon or other clinician to retract the firing system if it becomes stuck and / or malfunctions.

[0025] Further details regarding surgical stapling and cutting devices 100 and other surgical stapling and cutting devices suitable for use with the present disclosure are described, for example, in U.S. Patent No. 9,332,984 and U.S. Patent Application Publication No. 2009 / 0090763, which are incorporated herein by reference in their entirety. Furthermore, surgical stapling and cutting devices do not need to include a handle and instead may have a housing configured to be coupled to a surgical robot, as described, for example, in U.S. Patent Application Publication No. 2019 / 0059889, which are also incorporated herein by reference in their entirety.

[0026] As further shown in Figure 1, the staple cartridge 200 can be used with the apparatus 100. When in use, the staple cartridge 200 is positioned and connected within the elongated channel 104. The staple cartridge 200 can have various configurations, but in this illustrated embodiment, the staple cartridge 200 shown in detail in Figures 2A and 2B has a proximal end 202a and a distal end 202b, with the longitudinal axis (LC) of the cartridge extending between the proximal end 202a and the distal end 202b. As a result, when the staple cartridge 200 is inserted into the elongated channel 104 (Figure 1), the longitudinal axis (LC) is substantially or nearly parallel to the longitudinal axis (LS) of the elongated shaft 108. Furthermore, 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 launching member of a launching assembly, such as the launching assembly 400 in Figure 4, as will be discussed further below. As shown, the longitudinal slot 210 extends from the proximal end 202a to the distal end 202b of the staple cartridge 200. It is also intended herein that the longitudinal slot 210 may be omitted in other embodiments.

[0027] The illustrated staple cartridge 200 includes defined staple cavities 212, 214, each staple cavity 212, 214 configured to removably accommodate at least a portion of staples (not shown). The number, shape, and position of the staple cavities can vary and depend at least on the size and shape (e.g., mouth-like shape) of the staples removably disposed inside. In this illustrated example, the staple cavities are arranged in two sets of three longitudinal rows, with the staple cavities 212 of the first set located on the first side of the longitudinal slot 210, and the staple cavities 214 of the second set located on the second side of the longitudinal slot 210. On each side of the longitudinal slot 210, and therefore for each set of rows, the first longitudinal row of staple cavities 212a, 214a extends along the longitudinal slot 210, the second row of staple cavities 212b, 214b extends along the first row of staple cavities 212a, 214a, and the third row of staple cavities 212c, 214c extends along the second row of staple cavities 212b, 214b. Each row may be substantially parallel, and the staple cavities constituting the row may be oriented substantially parallel to the longitudinal slot 210. As shown in Figure 2A, each staple cavity 212, 214 may include a maximum length SL of about 0.122 inches to about 0.124 inches and a maximum width SW of about 0.023 inches to about 0.027 inches. Furthermore, at least the centers of the two adjacent cavities 212 and 214 are spaced approximately 0.158 inches apart.

[0028] Staples stored in the staple cavities 212, 214 in a deployable manner can have various configurations. An exemplary staple 300 that can be stored in each of the staple cavities 212, 214 is shown in its un-launched (pre-deposited, unformed) configuration in Figure 3. The illustrated staple 300 includes a crown (base) 302 and two legs 304 extending from each end of the crown 302, respectively. In this example, the crown 302 extends linearly, and the staple legs 304 have the same unformed height. Furthermore, before the staple 300 is deposited, the staple crown 302 can be supported by a staple driver positioned within the staple cartridge 200, and at the same time, the staple legs 304 can be at least partially housed within the staple cavities 212, 214. Furthermore, the staple leg 304 can extend beyond the upper surface, such as the upper surface 206 of the staple cartridge 200, when the staple 300 is in the non-firing position. In certain circumstances, as shown in Figure 3, the tip 306 of the staple leg 304 can be sharp and pointed, capable of cutting and penetrating tissue.

[0029] During use, the staple 300 can be deformed from an unfired position to a firing 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 deform relative to the anvil 102, the legs 304 of each staple 300 can capture a portion of the tissue within each staple 300 and apply compressive force to the tissue. Furthermore, the legs 304 of each staple 300 can deform downward toward the crown 302 of the staple 300 to form a staple capture region into which tissue can be captured. In various cases, the staple capture region may be defined between the inner surface of the deformed leg and the inner surface of the crown of the staple. The size of the staple capture region may depend on several factors, such as the length of the leg, the diameter of the leg, the width of the crown, and / or the degree of leg deformation.

[0030] In some embodiments, all staples disposed within the staple cartridge 200 may have the same unfired (pre-deposited, unformed) configuration. In other embodiments, the staples may include at least two groups of staples, each having different unfired (pre-deposited, unformed) configurations, such as differing in height and / or shape from one another.

[0031] Referring again to Figures 2A and 2B, the staple cartridge 200 extends from the top or deck surface 206 to the bottom surface 208, with the top surface 206 configured as the surface facing the tissue and the bottom surface 208 configured as the surface facing the channel. As a result, as shown in Figure 1, when the staple cartridge 200 is inserted into the elongated channel 104, the top surface 206 faces the anvil 102 and the bottom surface 208 (which is obscured) faces the elongated channel 104.

[0032] Referring to Figures 4 and 5, a launch assembly, such as launch assembly 400, can be used in conjunction with a surgical staple fastening and cutting device, such as device 100 in Figure 1. The launch assembly 400 may be configured to advance a wedge thread 500, which has a wedge 502 configured to deposit staples from a staple cartridge 200, into tissue trapped between an anvil, such as an anvil 102 in Figure 1, and a staple cartridge, such as the staple cartridge 200 in Figure 1. Furthermore, an E-shaped beam section 402 at the distal portion of the launch assembly 400 may launch staples from the staple cartridge. During launch, the E-shaped beam section 402 can also pivot the anvil toward the staple cartridge, and thus move the end effector from an open position to a closed position. The illustrated E-shaped beam section 402 includes a pair of upper pins 404, a pair of intermediate pins 406 which may be along a portion 504 of the wedge thread 500, and a lower pin or foot 408. The E-shaped beam section 402 may also include a sharp cutting edge 410 configured to cut captured tissue as the launch assembly 400 advances distally, and thus toward the distal end of the staple cartridge. In addition, an upper guide 412 and an intermediate guide 414 integrally molded to sandwich each vertical end of the cutting edge 410 and projecting proximal, may further define a tissue staging area 416 that assists in guiding tissue toward the sharp cutting edge 410 before cutting the tissue. The intermediate guide 414 may also function to engage with and launch staples in the staple cartridge by abutting a stepped central member 506 of the wedge thread 500, which enables staple forming by the end effector 106.

[0033] During use, the anvil 102 in Figure 1 is moved to the closed position by pressing down the closing trigger in Figure 1, which advances the E-shaped beam section 402 in Figure 4. The anvil 102 can position the tissue relative to at least the upper surface 206 of the staple cartridge 200 in Figures 2A and 2B. Once the anvil is properly positioned, the staples 300 in Figure 3, which are arranged inside the staple cartridge, can be held in place.

[0034] To implant staples from the staple cartridge, as described above, the thread 500 in Figure 5 can be moved from the proximal end to the distal end of the cartridge body, and therefore from the proximal end to the distal end of the staple cartridge. As the firing assembly 400 in Figure 4 advances, the thread can contact the staple driver in the staple cartridge and lift it upward within the staple cavities 212, 214. In at least one example, the thread and staple driver may each include one or more inclined surfaces, i.e., beveled surfaces, which work together to move the staple driver upward from its unfired position. Once the staple driver is lifted upward within each staple cavity, the staple advances upward, exiting the staple cavity and penetrating into the tissue. In various cases, the thread may move several staples upward simultaneously as part of the firing sequence.

[0035] As described above, the stapling device can be used in combination with a compressible auxiliary material. While such auxiliary materials are shown and described below, those skilled in the art will understand that the auxiliary materials disclosed herein can be used with other surgical instruments and do not need to be connected to a stapling cartridge as described. Furthermore, those skilled in the art will understand that the stapling cartridge does not need to be replaceable.

[0036] As mentioned above, with some surgical staplers, surgeons are often required to select the appropriate staple with the appropriate staple height for the tissue being stapled. For example, surgeons use tall staples for thick tissue and short staples for thin tissue. However, in some situations, the stapled tissue does not have a consistent thickness, and therefore the staple cannot achieve the desired post-launch configuration for all parts of the stapled tissue (e.g., parts of thick tissue and parts of thin tissue). If staples of the same or substantially higher height are used due to the inconsistent thickness of the tissue, undesirable leakage and / or tearing of the tissue may occur at the staple site, especially if the staple site is exposed to internal pressure at that site and / or along the row of staples.

[0037] Accordingly, various embodiments of auxiliary materials are provided that can be configured to compensate for varying thicknesses of tissue captured within fired (implanted) staples, thereby avoiding the need to consider staple height when stapling tissue during surgery. That is, the auxiliary materials described herein can also, in combination with the auxiliary material, provide appropriate tissue compression within and between fired staples, while enabling the use of a set of staples of the same or similar height when stapling tissue of varying thicknesses (e.g., from thin to thick tissue). Thus, the auxiliary materials described herein can maintain suitable compression for thin or thick stapled tissue, thereby minimizing leakage and / or tearing of tissue at the staple site. In addition, the exemplary auxiliary materials described herein may be configured to be absorbed into the body over a period of 100 to 300 days, depending on the implanted location and the health of the tissue.

[0038] Alternatively, or in addition, the implantable material may be configured to promote tissue endografting. In various situations, it is desirable to promote tissue endografting into the implantable implant to accelerate the healing of the tissue being treated (e.g., stapled and / or incised tissue) and / or to accelerate the patient's recovery. More specifically, tissue endografting into the implantable implant may reduce the incidence, severity, and / or duration of inflammation at the surgical site. Tissue endografting into and / or around the implantable implant may, for example, control the spread of infection at the surgical site. For example, vascular, particularly leukocyte, endografting into and / or around the implantable implant may combat infection in and around the implantable implant and adjacent tissue. Tissue endografting may also assist the patient's body in accepting foreign bodies (e.g., implantable implants and staples) and reduce the likelihood of the patient's body rejecting foreign bodies. Rejection of foreign bodies can lead to infection and / or inflammation at the surgical site.

[0039] Generally, the auxiliary materials provided herein are designed and positioned on top of a staple cartridge, such as a staple cartridge 200. When a staple is fired (implanted) from the cartridge, the staple penetrates the auxiliary material and enters the tissue. When the legs of the staple are deformed upon contact with an anvil positioned on the opposite side of the staple cartridge, the deformed legs capture a portion of the auxiliary material and a portion of the tissue within each staple. That is, when a staple is fired into the tissue, at least a portion of the auxiliary material is positioned between the tissue and the fired staple. While the auxiliary materials described herein may be configured to be attached to a staple cartridge, it is also intended herein that the auxiliary materials may be configured to mate with components of other instruments, such as an anvil for a surgical stapler. Those skilled in the art will understand that the auxiliary materials provided herein may be used for reloading staples that are not replaceable cartridges or cartridge-based.

[0040] In various embodiments, the auxiliary materials or bioabsorbable materials disclosed herein may consist of absorbent polymers. In certain embodiments, the auxiliary materials may consist of foams, films, fibrous fabrics, fibrous nonwoven polyurethanes, polyether urethanes, polyester urethanes, polyester urea, polyesters, polycarbonates, polyorthoesters, polyanhydrides, polyesteramides, polyphosphazenes, polyphosphoesters, polysaccharides, and / or polyoxaesters. In other embodiments, the auxiliary materials may be copolymers including, for example, PGA (polyglycolic acid), PGA / PCL (poly(glycolic acid-co-caprolactone)), PLA / PCL (poly(lactic acid-co-polycaprolactone)), PLLA / PCL, PGA / TMC (poly(glycolic acid-co-trimethylene carbonate)), PDS, PEPBO, and the like. In various embodiments, the auxiliary materials may include, for example, organic materials such as carboxymethylcellulose, sodium alginate, hyaluronic acid, and / or oxidized regenerated cellulose. In various embodiments, the auxiliary material has a juroty hardness in the range of 3 to 7 Shore A (30 to 50 Shore 00) with a maximum stiffness of 15 Shore A (65 Shore 00). In certain embodiments, the auxiliary material can undergo, for example, 40% compression under a load of 3 lbf, 60% compression under a load of 6 lbf, and / or 80% compression under a load of 20 lbf. In certain embodiments, one or more gases, such as air, nitrogen, carbon dioxide, and / or oxygen, can be passed through the auxiliary material and / or contained within the auxiliary material.

[0041] How to staple tissue Figures 6A and 6B show exemplary examples of a staple fastening assembly 600 including a staple cartridge 200 and an auxiliary material 604. For simplicity, the auxiliary material 604 is schematically shown in Figures 6A and 6B, and various configurations of the auxiliary material will be described in more detail below. As shown, the auxiliary material 604 is positioned relative to the staple cartridge 200. Although partially obscured in Figures 6A and 6B, the staple cartridge 200 includes staples 300 configured to be implanted within the tissue. The staples 300 can have any preferred unformed (pre-implantation) height.

[0042] In the illustrated examples, the auxiliary material 604 can be fitted to at least a portion of the top surface or deck surface 206 of the staple cartridge 602. In some embodiments, the top surface 206 of the staple cartridge 200 may include one or more surface features that engage with the auxiliary material 604 and are configured to prevent undesirable movement of the auxiliary material 604 relative to the staple cartridge 200 and / or prevent premature release of the auxiliary material 604 from the staple cartridge 200. Exemplary surface features are described further later and are included herein by reference in their entirety in U.S. Patent No. 10,052,104.

[0043] Figure 6B shows a staple fastening assembly 600 positioned within and connected to the elongated channel 610 of the surgical end effector 106. The anvil 102 is pivotally connected to the elongated channel 610 and is therefore movable between an open position and a closed position relative to the elongated channel 610, and thus to the staple cartridge 200. The anvil 102 is shown in the closed position in Figure 6B, and the interstitial gap T formed between the staple cartridge 602 and the anvil 612 is visible. G1 This shows that. More specifically, the interstitial space T G1The intercellular gap T is defined by the distance between the microstructure compression surface 102a of the anvil 102 (e.g., the microstructure engagement surface between staple-forming pockets within the anvil) and the microstructure contact surface 604a of the auxiliary material 604. In this illustrated example, both the microstructure compression surface 102a of the anvil 102 and the microstructure contact surface 604a of the auxiliary material 604 are planar or substantially planar (e.g., planar within manufacturing tolerances). As a result, when the anvil 102 is in the closed position, the intercellular gap T is defined as shown in Figure 6B. G1 When no tissue is present within it, it is generally uniform (for example, nominally identical within manufacturing tolerances). In other words, the inter-tissue gap T G1 The distance across the end effector 106 (e.g., in the y-direction) is generally constant (e.g., constant within manufacturing tolerances). In other embodiments, the microstructure compression surface of the anvil includes a stepped surface having longitudinal steps between adjacent longitudinal portions, and thus a stepped profile can be formed (e.g., in the y-direction). In such examples, the microstructure gap T G1 It can fluctuate.

[0044] The auxiliary material 604 is compressible, and can be compressed to various heights to compensate for the different tissue thicknesses captured within the implanted staple. The auxiliary material 604 has an uncompressed (undeformed) or pre-implantation height and is configured to deform to one of several compressed (deformed) or implantation heights. For example, the auxiliary material 604 may have an uncompressed height that is higher than the post-launch height of the staple 300 disposed within the staple cartridge 200 (e.g., the height (H) of the post-launch staple 300a in Figure 7A). That is, the auxiliary material 604 may have an undeformed state in which the maximum height of the auxiliary material 604 is higher than the maximum height of the launched staple (e.g., the staple in the molded configuration).

[0045] During use, when a surgical stapling and cutting device such as device 100 of FIG. 1 is oriented towards the surgical site, the anvil 102 is positioned adjacent to the first side of the tissue and the stapling assembly 600 is positioned adjacent to the second side of the tissue, such that the tissue is positioned between the anvil 102 and the stapling assembly 600 (e.g., the tissue can be positioned against the tissue contact surface 604a of the insert 604). When the tissue is positioned between the anvil 102 and the stapling assembly 600, the surgical stapler is actuated, for example as described above, thereby clamping the tissue between the anvil 102 and the stapling assembly 600 (e.g., between the tissue compression surface 102a of the anvil 102 and the tissue contact surface 604a of the insert 604), and staples can be placed through the insert from the cartridge into the tissue to staple and attach the insert to the tissue.

[0046] As shown in FIG. 7A, when the staple 300 is fired, a portion of the tissue (T) and the insert 604 is captured by the fired (formed) staple 300a. Each of the fired staples 300a defines a capture region therein, as described above, for accommodating the captured insert 604 and tissue (T). The capture region defined by the fired staples 300a is at least partially limited by the height (H) of the fired staples 300a.

[0047] Referring to FIG. 7B, the insert 604 can have apertures 632 having a median pore diameter of, for example, about 0.025 mm 3 such as about 0.022 mm 3 to about 0.300 mm. 3 In some embodiments, the insert 604 can have one or more struts 634 between the apertures 632 that provide support and strength to the insert 604. Specifically, the insert 604 can include a plurality of struts 634 having a median strut thickness ST of from about 0.025 mm to about 0.300 mm, such as about 0.08 mm.

[0048] Figure 8 shows a perspective view of a staple cartridge assembly 600 having an auxiliary material 604 and a staple cartridge 200. The auxiliary material 604 has a tissue contact surface 604a, a proximal end 604c, and a distal end 604b. The auxiliary material 604 may include a slot / slit 808 that separates or partially separates two parallel portions of the auxiliary material 604. In one example, the auxiliary material 604 may include a slot 808 that separates two parallel portions of the auxiliary material 604, while in another example, the auxiliary material 604 may include a slit 808 that separates two parallel portions of the auxiliary material 604, and one or more bridges (e.g., five bridges) 802 that connect the two parallel portions of the auxiliary material 604. At least one bridge has a longitudinal length of about 0.035 inches to about 0.046 inches. The auxiliary material 604 has a length L of approximately 40 mm to approximately 80 mm, such as approximately 60 mm to approximately 65 mm, approximately 66.04 mm to approximately 66.3 mm, approximately 45 mm to approximately 55 mm, or approximately 51.12 mm to approximately 51.38 mm. The auxiliary material 604 has a width W of approximately 8 mm to approximately 12 mm, such as approximately 9.75 mm to approximately 10.25 mm or approximately 10.025 mm to approximately 10.035 mm. The auxiliary material 604 may also have a thickness or height TH of approximately 2.5 mm to approximately 3.5 mm, for example, approximately 2.85 mm to approximately 3.15 mm, or approximately 2.95 mm to approximately 3.05 mm.

[0049] Cartridge 200 has a height CH of approximately 6.3 mm to approximately 8.1 mm, a width CW of approximately 8.9 mm to approximately 14 mm, and a length CL of approximately 80 mm to approximately 90 mm, for example, approximately 86.7 mm.

[0050] The staple cartridge 200 may include one or more raised ledges 804 along one or more sides of the auxiliary material 604 to help align the auxiliary material 604 on the deck of the staple cartridge 200. Although not shown in Figure 8, the staple cartridge 200 may also include an adhesive or buttress adhesive material for attaching the auxiliary material 604. The auxiliary material 604 may be attached to the cartridge 200 using about 100 mg to about 120 mg of the adhesive or buttress adhesive material.

[0051] Adjustable absorption pathways for bioabsorbable materials Balancing the depletion of mechanical properties with the skeletal absorption of the augment material after delivery can be improved by a two-phase decomposition mechanism. As described above, the end effector 106 (shown in Figure 1), comprising the cartridge 200 and the augment material 604, is closed or substantially closed for insertion into the delivery site through the trocar. Therefore, the surgical augment material 604 must have mechanical properties such that the material is sufficiently compressible for insertion through the trocar during delivery, but must also have high strength to hold staples, sutures, and screws at the delivery site. In addition, the surgical augment material 604 must be bioabsorbable so that it remains at the target site after delivery until the tissue can adequately maintain the hemostatic seal and / or until the tissue has fully healed. From a mechanical standpoint, the augment material 604 provides an ideal amount of compression that is strong enough to form and maintain a hemostatic seal, but not excessively compressed or too strong, allowing for staple firing during delivery. A short-term absorption profile may be preferable for hemostasis, while a long-term absorption profile may be better suited for better tissue healing without leakage.

[0052] Referring to Figures 9A and 9B, an exemplary staple cartridge assembly 900 includes an end effector 106 having a surgical aid 604 and a staple cartridge 200. The surgical aid 604 may consist of a substantially monolithic structure. In addition, the aid 604 may be a bioabsorbable material comprising a first polymerizable compound having a first degradation profile. The material selection of the first polymerizable compound may be a reaction product of a polyol and an isocyanate, e.g., polyurethane or similar polymers (including, but not limited to, polyether urethane, polyester urethane, polyester urea, polyester, polycarbonate, polyorthoester, polyanhydride, polyesteramide, polyphosphazene, polyphosphoester, polysaccharide, and / or polyoxaester). The polyurethane reaction product may have a degradation profile tailored to the target tissue site. The surgical aid 604 may have one or more of the following properties that are modulated for specific purposes before, during, and after surgical procedures, and that modify its mechanical properties. In particular, the described auxiliary material 604 has selective crosslinking density control in vivo and can also have specific compressibility when attached to a cartridge outside of the body.

[0053] In some embodiments, the first polymerizable compound may be a reaction product of a polyol and an isocyanate, forming a polyurethane or polyurethane derivative. The polyurethane is configured to degrade according to the first degradation profile. The aliphatic polyurethane is absorbed primarily by oxidative and / or enzymatic mechanisms. A second polymerizable compound is added to adjust the absorption profile after delivery, minutes, hours, days, or weeks, while maintaining the mechanical properties at staple firing. The second polymerizable compound is configured to degrade according to the second degradation profile. In some embodiments, the second polymerizable compound can adjust the absorption induction period, thereby delaying the bulk absorption of the auxiliary material 604. In some cases, physiological conditions at the delivery site may be used to accelerate the absorption of at least one of the first polymerizable compound and / or the second polymerizable compound.

[0054] As described herein, surgical adjuvants 604 may be formulated for specific purposes before, during, and after surgical procedures. Adjuvants 604 comprise a first polymerizable compound having a first degradation profile and a second polymerizable compound having a second degradation profile different from that of the first. In particular, the described adjuvants 604 may be polymers having tunable absorption properties via alternating copolymers, random copolymers, block copolymers, multiblock copolymer structures, terpolymers, graft copolymers (monomer skeletons having pendant chains of different monomers), bulk homopolymers coated with the second homopolymer, and the like.

[0055] In some embodiments, the second polymerizable compound may be polyester, poloxamer, polymethacrylate, polyether, polydioxanone, polyanhydride, hydroxypropyl methylcellulose acetate succinate, cellulose acetate phthalate, cellulose acetate trimellitate, hydroxypropyl methylcellulose phthalate, polyvinyl acetate phthalate, poly(trimethylene carbonate), poly(beta-thioether ester ketal), polypropylene fumarate, poly(ester urea), or poly(ester amide).

[0056] In some embodiments, the first polymerizable compound alone has a suitable degradation profile for tissue healing within about six weeks. In some embodiments, it is desirable to adjust the degradation profile of the auxiliary material 604 for a longer degradation profile. In some embodiments, the bioavailability rate of the auxiliary material 604 can be adjusted by adding more or less of the second polymerizable compound to the first polymerizable compound. Generally, the auxiliary material 604 can have the first polymerizable compound in approximately equal proportions to the second polymerizable compound. In certain other embodiments, the volume ratio of the first polymerizable compound to the second polymerizable compound may be in the range of about 10:0.1 to about 0.1:10. For example, if a longer degradation profile is desired, the volume ratio may be about 10:1, about 10:2, about 10:3, or about 10:4. As another non-limiting example, to adjust the degradation profile to a shorter period, the volume ratio may be about 1:10, about 2:10, about 3:10, or about 4:10. As those skilled in the art will understand, the overall decomposition profile of the auxiliary material can be adjusted by adjusting the type, molecular weight, and amount of the first polymerizable compound relative to the second polymerizable compound.

[0057] In some embodiments, a second polymerizable compound may be added to the polyurethane skeleton such that the first polymerizable compound and the second polymerizable compound jointly form a copolymer skeleton. When a second polymerizable compound is added to the polyurethane skeleton, the second polymerizable compound may be one of a polyol or an isocyanate. For example, the second polymerizable compound may be a polyester polyol that, when added to the first polymerizable compound, can replace the polyol in the polyurethane reaction product to form a block copolymer or an alternating copolymer. Alternatively, or in addition to the above, a polyester polyol may also be added to the polyol in the polyurethane reaction product to introduce multiple polyol monomers into the polyurethane skeleton, for example, in a block copolymer (ABA type) or a random copolymer.

[0058] By including an aliphatic polyester polyol as a second polymerizable compound, another degree of freedom can be added to the polyurethane backbone, allowing for adjustment of the absorption and mechanical properties of the auxiliary material 604. Beyond a certain molecular weight, mechanical strengthening may occur through crystallization, which effectively adds crosslinks to the polyurethane system, thereby reducing the overall number of covalent crosslinks. Generally, a reduction in the number of covalent crosslinks can accelerate the degradation profile of the auxiliary material 604.

[0059] In addition to changes in crosslink density, the addition of a second polymerizable compound, such as a polyester polyol, can increase the sensitivity of the skeleton to the hydrolysis mechanism of absorption. Under the hydrolysis pathway, sensitivity to acidic conditions can be used to preferentially increase the absorption rate or decomposition profile of auxiliary material 604 in the presence of lower pH.

[0060] Typical polyester polyols have a branched structure and a weight-average molecular weight (M w) is 2,000 to 10,000. Polyester polyols are typically produced from a mixture of diols, triols, and dibasic acids or anhydrides. Polyether polyols are produced by the reaction of epoxides with compounds having active hydrogen atoms. Polyester polyols are produced by the polycondensation reaction of polyfunctional carboxylic acids with polyhydroxyl compounds. Examples of polyester polyol monomers, but not limited to, include poly(hexamethylene adipate) (PHA), aminocaproic acid, hexamethylenediamine adipate (1:1), 6-aminohexanoate, 1,4-butanediamine adipate, hexanediamine undecane-1,11-diamine hexanediate, 6-diaminohexanoic acid, bis(6-aminohexanoic acid)calcium, 6-aminohexanoyloxidanium, 6-aminohexanoic acid, octane-1, 8-Diaminehexanodic acid, ethane-1,1,2-triaminehexanodic acid, pentane-1,5-diamineheptanedic acid, hexane-1,1-diaminehexanodic acid, butane-1,1-diaminehexanodic acid, (2S)-2,6-diaminohexanoic acid hexanodic acid, heptane-1,6-diaminehexanodic acid, 2-aminoacetic acid 2,6-diaminohexanoic acid, 2,6-diaminohexanoic acid hexanodic acid, 2-aminoacetic acid (2S)-2,6-diaminohexanoic acid Acids, cadaverine adipic acid, cadaverine adipic acid dihydrate, nonane-1,9-diamine hexanedioxide, 6-aminocaproic acid-d6, 6-amino-2,2,6,6-tetraduteriohexanoic acid, 6-aminohexanoic acid butanediic acid, 6-amino-6,6-diduteriohexanoic acid, 6-amino-2,2-diduteriohexanoic acid, propane-1-amine hexanedioxide, hexane-1,6-diamineoctanediic acid, hexane 6-aminohexanoic acid Diacids, 6-(6-aminohexanoyloxy)-6-oxohexanoic acid, hexane-1-aminehexanodic acid, 6-aminohexanoic acid carbamic acid, 2-aminoacetic acid 6-aminohexanoic acid, 6-aminohexanoic acid 3-aminopropanoic acid, ethane-1,2-diaminehexanodic acid, 7-aminoheptanoic acid hexane-1,6-diamine, 6-aminohexanoic acid (2S)-2,6-diaminohexanoic acid, 6-aminohexanoic acid 3-aminopropanoic acid, butane-1,4-Diamineheptanediic acid, 6-amino-6-oxohexanoate hexane-1,6-diamine, 6-aminohexanoic acid acetate, 6-aminohexanoate azan, ethaneaminehexanediic acid, 4-aminobutanoic acid 6-aminohexanoic acid, 6-aminohexanoyl 6-aminohexanoperoxoate, 6-aminohexanoate ethane-1,2-diamine, hexanediic acid 5-azaniummylpentylazanium, heptane-1,1-diaminehexanediic acid, aminohexanoate 6-aminohexanoic acid, decane-1,10-dia Minhexanoic acid, ethane-1,2-diaminehexanoic acid, 6-hexanoic acid azanium-mylhexyl azanium-hexanoic acid, 6-(dijuterioamino)hexanoic acid, 7-aminoheptanoic acid 6-aminohexanoic acid, hexane-1,5-diaminehexanoic acid, 6-aminohexanoic acid hexanoic acid, hexamethylenediammonium-adipato-dihydrato, tetramethylenediammonium adipate, 6-aminohexanoic acid hexane-1,6-diamine, 6-(4-aminobutylamino)oxy-6-oxohexa 6-hydroxyhexanoic acid, hexane-1,6-diamine 6-hydroxyhexanoic acid, hexane dioxide 6-azanium-mylhexyl azanium hydrate, 6-aminohexanoic acid hydrate, 6-aminohexanoic acid methylidenazanium, 6-aminohexanoic acid ethane molecular hydrogen, 6-aminohexanoic acid methaneamine, heptane-1,7-diamineheptanedioic acid, 6-aminohexanoic acid ethanefermium cyanide, 5-carboxypentyl asanide, 6-(6-aminohexylamino)oxy-6-oxohexanoic acid, 6-aminohexanoic acid zinc, Pentane-1,5-diamine octanodioate, azanium 6-aminohexanoic acid, 2,6-diaminohexanoic acid 6-aminohexanoic acid, hexa-1,6-diaminehexanoic acid carbamate, methane 6-(6-aminohexylamino)oxy-6-oxohexanoic acid, azanium hexanidioate 6-azaniumylhexylazanium, butane-1-aminehexanoic acid, heptane-1-aminehexanoic acid, 8-aminooctanoic acid 6-aminohexanoic acid, heptanedioic acid 7-aminoheptanoic acid, pentane-1 hexanoic acidExamples include 1-diamines, N-(6-aminohexyl)hydroxylaminehexanoate, 6-azaniummylhexylazaniumhexanoate, 6-aminohexanoate ethane, 6-aminohexanoic acid hydrate, 7-azaniumheptylazanium hexanoate, butane-1,4-diaminehexanoic acid, 4-aminobutanoic acid, 6-aminohexanoic acid, 3-aminopropanoic acid, and 6-aminohexanoate.

[0061] In some embodiments, auxiliary material 604 having hydroxy-terminated polymer chains can improve the biodegradation profile. A stoichiometric excess of hydroxyl relative to the carboxylic acid functional group ensures that the final polymer is hydroxy-terminated, while an excess of carboxyl results in a carboxylic acid-terminated polyester. Branching can be incorporated into the polyester backbone using trifunctional monomers such as trimethylolpropane, 2,2-di(hydroxymethyl)-1-butanol, or trimellitic anhydride.

[0062] Polyether polyols are the most common type of polyol. Polyether polyols are produced by the reaction of epoxides with compounds containing active hydrogen atoms. Typical polyester polyols have a low glass transition temperature (T). gIt possesses a property that provides good retention of physical properties and impact resistance at very low temperatures. Generally, polyether-based polyurethane exhibits higher resilience (elasticity) compared to polyester-based polyurethane. Examples of polyether polyol monomers include, but are not limited to, polyethylene glycol, polytetramethylene ether glycol, polypropylene oxide glycol, polybutylene oxide glycol, triethylene glycol monoethyl ether, 1,2-diethoxyethane 2-[2-(2-methoxyethoxy)ethoxy]ethanol, 1,2-diethoxyethane 2-methoxyethanol, 2-[2-[2-(2-hydroxyethoxy)ethoxy]ethoxy]ethanolmethane, 1-ethoxy-2-methoxyethane 2-methoxyethanol, methane 2-[2-(2-methoxyethoxy)ethoxy]ethanol hydrate, methanol 2-[2-(2-methoxyethoxy)ethoxy]ethanol, 2-(2-(2-(2-(2-(2-ethoxyethoxy)ethoxy)ethoxy)ethoxy)ethanol, 2-[2-(2-ethoxyethoxy)ethoxy]ethanol hydrate , 2,5,8,11-tetraoxatridecane-13-ol, 2-(2-{2-[2-(2-methoxyethoxy)-ethoxy]ethoxy}ethoxy)ethanol, 2,5,8,11,14,17-hexaoxanonadecane-19-ol, 3,6,9,12-tetraoxatetradecane-1-ol, 3,6,9,12,15-pentaoxaheptadecane-1-ol, 4,7,10,13-tetraoxa-1-oxoniacyclopentade Can, pentaethylene glycol-water, 2-[2-[2-[2-(2-ethoxyethoxy)ethoxy]ethoxy]ethoxy]ethanol, butaneethane-1,2-diol 2-propoxyethanol, butane 2-ethoxyethanol, ethanol, mixture with 2,2'-[1,2-ethanediylbis(oxy)]bis-, 2,2'-oxybis[ethanol], 3,6,9,12,15-pentaoxaoctadecane-1-ol, 3,6,9,12-Tetraoxapentadecane-1-ol, 2-(2-(2-propoxyethoxy)ethoxy)ethanol, pentaethylene glycol, hexaethylene glycol, tetraethylene glycol, triethylene glycol monomethyl ether, sodium 1,4,7,10,13,16-hexaoxoniacyclooctadecane, sodium 1,4,7,10,13-pentaoxoniacyclopentadecane, sodium 1,4,7,10- Tetraoxoniacyclododecane, potassium 1,4,7,10,13-pentaoxoniacyclopentadecane, ytterbium 2-methoxyethoxide, cerium 2-methoxyethoxide, 2-[2-[2-(2-propoxyethoxy)ethoxy]ethoxy]ethanol, neodymium methoxyethoxide, erbium methoxyethoxide, ethanol 2-(2-hydroxyethoxy)ethanolpentane, butylcarbitol water, 2-[2-[2 -(2-hydroxyethoxy)ethoxy]ethoxy]ethyl hypofluorite, lanthanum methoxyethoxide, 2-[2-(2-butoxyethoxy)ethoxy]ethanolpropane, potassium 1,4,7,10,13,16-hexaoxoniacyclooctadecane, 2-[2-[2-[2-(2-hydroxyethinoxy)ethoxy]ethoxy]ethoxy]ethanol, 3,6,9,12,15,18-hexaoxahenicosan-1-ol, Examples include triethylene glycol-water, yttrium methoxyethoxide, heptaethylene glycol monomethyl ether, 2-(2-(2-ethoxyethoxy)ethoxy), 3,6,9,12,15,18-hexaoxaicosan-1,20-diol, 3,6,9,12,15-pentaoxanadecane-1-ol, 3,6,9,12-tetraoxahexadecane-1-ol, and triethylene glycol monobutyl ether.

[0063] By adding portions of auxiliary material 604 having varying degrees of hydrophilicity, it is possible to enable the auxiliary material to undergo a phase transition when exposed to a fluid. As hydrophilicity increases, the auxiliary material transitions from surface decomposition to bulk decomposition due to increased water penetration. In some embodiments, as the fluid swells the network, materials having the same polarity as the polymer may pass the lower critical solution temperature (LCST). Generally, the LCST is the critical temperature below which the components of the mixture become miscible in all proportions. In some embodiments, the polymer system in solution has an LCST at a temperature higher than the upper critical solution temperature (UCST), meaning that a temperature interval of complete miscibility exists, with partial miscibility at both higher and lower temperatures. The UCST is the critical temperature above which the components of the mixture become miscible in all proportions.

[0064] For polymers in solutions or fluids, LCST (Liquid-Cold Temperature) depends on the degree of polymerization, polydispersity, branching, composition, and structure of the polymer. Below LCST, the polymer portion in the solution or fluid is completely miscible in all proportions, but above LCST, partial liquid miscibility occurs.

[0065] In some embodiments, the auxiliary material 604 may include specific segments of a block copolymer having an LCST in the range of about 20°C to about 35°C. This allows at least a portion of the auxiliary material to undergo a phase transition at a lower temperature compared to the polyurethane backbone. Upon passing through the LCST, one of the polar or nonpolar portions of the auxiliary material can micellize, forming effective crosslinks within the system. In this way, the increase in fluid content due to fluid intrusion can cause the auxiliary material to undergo a phase transition from one phase to two phases and then back to one phase. During the one-phase miscibility period, the auxiliary material 604 has low mechanical strength, which is desirable during deposition. During the two-phase immiscibility period, the fluid is absorbed by the auxiliary material 604, and the mechanical strength increases as the crosslinks effectively increase, counteracting the decomposition of the auxiliary material 604. Upon reaching a critical level, the crosslinks may break, and the mechanical strength of the auxiliary material decreases. Since reversible crosslinks exist at the critical stage of the healing process, this phase transition allows for both low deposition force and faster absorption of the auxiliary material.

[0066] In some embodiments, the second polymerizable compound may be a poloxamer added to the polyurethane backbone. Poloxamers are a class of water-soluble, nonionic triblock copolymers formed by polar (polyethylene oxide) blocks and non-polar (polypropylene oxide) blocks. Poloxamers can impart amphiphilic and surfactant properties to the polymer backbone. In some embodiments, a faster absorption rate can be facilitated by increasing the penetration of water into the polar portion of the auxiliary material 604. The LCST depends on the length and relative water content of the polypropylene oxide segment.

[0067] In any embodiment described herein, a second polymerizable compound may be added to the backbone of a first polymerizable compound as a pendant group so that the second polymerizable compound forms a coating. The coating can act to prevent or delay fluid ingress into the first polymerizable compound.

[0068] In some embodiments, the second polymerizable compound can act as an enteric coating in the presence of gastric juice or near an infection. The coating may be resistant or substantially resistant to absorption at specific pH levels, such as acidic conditions (pH < 7), so that the coating can be used on tissues in or near the stomach. In other embodiments, the coating may delay the absorption time over a given time frame, preventing the bulk material of the auxiliary from coming into contact with the fluid. Gastric juice and infection fluids tend to have lower pH levels than other locations in the body. Using auxiliary material 604 with a second polymerizable compound that is resistant to degradation under acidic conditions may be beneficial when treating tissues near the stomach, gastrointestinal tract, or other acidic areas of the body. Generally, the retention of the mechanical strength of auxiliary material 604 is a function of absorption and fluid penetration. The second polymerizable compound can prevent or delay fluid penetration at lower pH levels. As the pH increases, the fluid can pass through the coating and initiate the degradation of the first polymerizable compound. The second polymerizable compound can be adjusted to have a specific induction period based on pH by adjusting its composition, thickness, branching, etc.

[0069] In some embodiments, the second polymerizable compound may be a polymethacrylate copolymer having a specific carboxylic acid functionalization. In addition, the second polymerizable compound may also include, but are not limited to, polydioxanone, polyanhydride, hydroxypropyl methylcellulose acetate succinate, cellulose acetate phthalate, cellulose acetate trimellitate, hydroxypropyl methylcellulose phthalate, polyvinyl acetate phthalate, poly(trimethylene carbonate), poly(beta-thioether ester ketal), polypropylene fumarate, poly(ester urea), poly(ester amide), or combinations thereof as copolymers with or without polymethacrylate.

[0070] In addition to a single enteric coating layer, a second polymerizable compound can also form a multilayer structure, providing further advantages independent of the local pH environment. In some embodiments, the second polymerizable compound can form an acid-generating surface of the auxiliary material so that the enteric coating is maintained as additional protons or acid species are generated. This extends the induction period provided by the enteric coating and further prevents any fluid intrusion. As the surface-eroding polymer decomposes to a critical point, fluid intrusion can proceed, for example, in the presence of a neutral pH in the enteric coating, allowing absorption of the stapled implant. In some embodiments, the multilayer structure may exist as a bilayer. In any embodiment described herein, the bilayer or multilayer structure may contain an active pharmaceutical ingredient (API) that can be released as the surface-eroding polymer decomposes. Examples of acid-generating polymers include, but are not limited to, polyanhydrides such as poly(carboxyphenoxyhexane-sebacic acid), poly(fumaric acid-sebacic acid), poly(imide-sebacic acid), and poly(imide-carboxyphenoxyhexane). Other acid-generating polymers may contain a 3-iodopropyl acetal moiety.

[0071] In some embodiments, if the second polymerizable compound forms a coating, the composition and / or thickness of the coating can provide an induction period for the absorption and / or decomposition process. The initial thickness of the second polymerizable compound coating prior to delivery and / or induction may be in the range of about 20 μm to about 100 μm (e.g., about 30 μm to about 90 μm, about 40 μm to about 60 μm, about 45 μm to about 50 μm, and any range in between). Upon exposure to temperature or pH, the thickness of the second polymerizable compound coating may increase in accordance with the tissue compression required to achieve hemostatic sealing.

[0072] As those skilled in the art will understand, the addition of the second polymerizable compound can be spatially controlled for optimal absorption, tissue proliferation, and / or hemostatic behavior. Furthermore, the compositions of the first and second polymerizable compounds can be gradients with various bioabsorption profiles along portions of the auxiliary material 604 (e.g., along length, at the center, at the ends, along the staple line, etc.). Generally, a short-term absorption profile may be preferred to address hemostasis, while a long-term absorption profile may address better tissue healing without leakage.

[0073] In some embodiments, the addition of a second polymerizable compound to the skeleton as a pendant group to the first polymerizable compound or as a coating can be carried out by any suitable technique, including but not limited to inkjet printing, direct deposition, thermal spraying, cold dynamic spraying, cold spraying, electrospraying, ultrasonic spray coating, immersion coating, screen printing, spin coating, solution deposition, stereolithography, and exterior lamination.

[0074] In some embodiments, the change in crosslinking density between the first polymerizable compound and the second polymerizable compound forms a compressive strength gradient along a portion of the auxiliary material 604. Generally, the auxiliary material 604 may have compressive strengths of about 20 kPa to about 70 kPa, such as about 30 kPa to about 60 kPa (e.g., about 42 kPa), about 30 kPa to about 50 kPa, and about 32.5 kPa to about 37.5 kPa. In some embodiments, the auxiliary material 604 may have a compressive strength of about 20 kPa to about 70 kPa due to a portion of the auxiliary material 604 having the first polymerizable compound, and a compressive strength of about 15 kPa to about 50 kPa due to a portion of the auxiliary material 604 having the second polymerizable compound.

[0075] In some embodiments, the auxiliary material 604 may have a tensile strength of approximately 30 kPa to approximately 90 kPa, such as approximately 45 kPa to approximately 85 kPa or approximately 55 kPa to approximately 75 kPa. In some embodiments, the auxiliary material 604 may have a tensile strength of approximately 110 kPa to approximately 150 kPa.

[0076] In any of the embodiments disclosed herein, an auxiliary material having a block copolymer with a first polymerizable compound and a second polymerizable compound can be used to modify the degradation profile of the auxiliary material (and the mechanical properties of the bioabsorbable material) over a predetermined time frame. For example, a phase transition may be undertaken over several seconds or minutes so that the porous body is easily compressible during delivery and the end effector is easily inserted through the trocar. After the induction period has elapsed, the mechanical strength of the auxiliary material 604 increases to allow for a suitable hemostatic seal between tissues. This increased mechanical strength after the induction period may range from about 10 minutes to about 6 weeks, which is the amount of time that may be required for the tissue to heal.

[0077] Returning to Figure 9A, the end effector 106 is shown in a delivery configuration in which the auxiliary material 604 is compressed between the anvil 102 and the cartridge 200. As shown, the end effector 106 may include a staple cartridge 200 and an auxiliary material 604 containing a bioabsorbable material. In certain embodiments, the auxiliary material 604 is releasedly held on the cartridge 200. When the end effector 106 closes around the tissue T, the auxiliary material 604 can be compressed from the thickness UT of the uncompressed auxiliary material to the thickness CT of the compressed auxiliary material, depending on the variation in tissue thickness.

[0078] Figure 9B is a side view of the end effector 106 after the staple 300 has been fired, and the auxiliary material 604 is no longer compressed between the anvil 102 and the cartridge 200. As shown, the auxiliary material 604 is released from the cartridge 200 after firing. The auxiliary material 604 is shown to maintain the thickness CT of the compressed auxiliary material and the thickness UT of the uncompressed auxiliary material from before firing in Figure 9A. In some embodiments, the auxiliary material 604 may undergo a phase transition before the staple is fired, and as a result, the height UT and compressed portion CT of the auxiliary material are maintained even after the firing and release of the auxiliary material 604 and tissue T. In other embodiments, the auxiliary material 604 may undergo a phase transition after a predetermined time, as described above. In such examples, the height UT and compressed portion CT of the auxiliary material may expand or contract depending on the staple height and tissue thickness. As will be understood by those skilled in the art, a phase transition of the auxiliary material 604 upon exposure to fluid intrusion may be advantageous in ensuring hemostatic sealing during changes in the tissue inflammatory response and throughout the healing process.

[0079] Figures 10A and 10B show a top and side view of the auxiliary material 604 after the staple 300 has been fired and the tissue T has been cut. The auxiliary material 604 may be split into two after firing, and the adhesive 1232 (see Figures 6A and 6B) that adheres the auxiliary material 604 to the cartridge 200 may, together with the auxiliary material 604, form ridges 604e, 604f and corresponding ridges 1232a within the auxiliary material. When the auxiliary material 604 is in contact with the tissue T, ridges 604e, 604f may be formed to correspond to variations in the texture and thickness of the tissue. This means that the auxiliary material 604 can adapt to different heights and compressions depending on the application.

[0080] Figures 11 and 12 are flowcharts of methods 1100 and 1200 for forming surgical adjuvants 604 containing bioabsorbable materials. The techniques described herein for modulating absorption pathways and altering mechanical properties may provide additional benefits, such as increased strength and durability of the adjuvants, when combined with positive in vivo interactions (e.g., biocompatibility, wound healing, tissue integration, chemotherapy, anti-inflammatory, bone growth and integration, ligament and tendon repair, etc.) as the adjuvants are delivered to the tissue site, as described herein. Thus, the techniques described herein may enable the bioabsorbable material itself to assist in the healing process of surrounding tissues. Furthermore, the implantation techniques described herein may provide additional benefits, such as preventing fibrous encapsulation of foam cushions and / or providing adjustable release profiles for various medical additives delivered to the tissue site.

[0081] Specifically with respect to Figure 11, Method 1100, used to modify the absorption pathway in a bioabsorbable material (e.g., a foam), may include chemically reacting a first polymerizable compound containing a reaction product of a polyol and an isocyanate configured to decompose according to a first decomposition profile (Step 1102). In some examples, the first polymerizable compound may include polyurethane, polyester urethane, polyester urea, polyester, polycarbonate, polyoltoester, polyanhydride, polyesteramide, polyphosphazene, polyphosphoester, polysaccharide, and / or polyoxaester. Method 1100 also includes adding a second polymerizable compound to the first polymerizable compound to form a copolymer backbone with the first polymerizable compound (Step 1104). The second polymerizable compound is configured to decompose according to a second decomposition profile. Following the introduction of the second polymerizable compound, Method 1100 includes exposing the auxiliary material to a fluid having at least one of a predetermined temperature (higher or lower), an enzyme-catalyst, or a predetermined pH (Step 1106). Method 1100 may be terminated after Step 1106, or optionally include adding a medical additive to the porous body (Optional Step 1108). In such an example, the medical additive may include agents for treating pain and / or for promoting wound healing, tissue growth, infection reduction, etc.

[0082] Figure 12, similar to Figure 11, includes Method 1200 used to modify the absorption pathway in a bioabsorbable material (e.g., a foam), but instead of forming a skeleton containing both the first and second polymerizable compounds in step 1104, Method 1200 includes adding the second polymerizable compound to the first polymerizable compound to form a coating around the skeleton (step 1204). The coating may be resistant or substantially resistant to absorption at a specific pH, such as acidic conditions (pH < 7), so that the coating can be used in the stomach or tissues near the stomach. In other embodiments, the coating may delay the absorption time over a given time frame and prevent the bulk material of the auxiliary material from coming into contact with the fluid. The first polymerizable compound can form the skeleton of the bioabsorbable material. As described above, the first polymerizable compound may include polyurethane, polyester urethane, polyester urea, polyester, polycarbonate, polyorthoester, polyanhydride, polyesteramide, polyphosphazene, polyphosphoester, polysaccharide, and / or polyoxaester. The second polymerizable compound is configured to decompose according to a second decomposition profile. After the introduction of the second polymerizable compound, Method 1200 includes exposing the auxiliary material to a fluid having at least one of a predetermined temperature, an enzyme-catalyst, or a predetermined pH (Step 1206). The second polymerizable compound can prevent or delay the penetration of the fluid at lower pH levels. As the pH increases, the fluid can pass through the coating and initiate the decomposition of the first polymerizable compound. Method 1200 can be terminated after Step 1206, or optionally include adding a medical additive to the porous material (Optional Step 1208).

[0083] As those skilled in the art will understand, the embodiments described above are by illustrative reference only, and the present invention is not limited to those specifically illustrated and described herein. Rather, the scope of the present invention includes both combinations and partial combinations thereof of the various features described herein, as well as variations and modifications thereof not disclosed in the prior art, which will be conceivable to those skilled in the art by reading the above description.

[0084] In some embodiments, the disclosed devices (e.g., end effectors, surgical aids, and / or staple cartridges), and methods involving one or more of the disclosed devices, may include one or more of the following provisions:

[0085] Clause 1: A bioabsorbable material configured to be delivered to tissue, comprising a reaction product of a polyol and an isocyanate, a first polymerizable compound configured to degrade according to a first degradation profile, and a second polymerizable compound configured to degrade according to a second degradation profile different from the first degradation profile, wherein the material undergoes a phase transition in response to exposure to a fluid having at least one of a predetermined temperature, an enzyme-catalyst, and a predetermined pH.

[0086] Clause 2: The material according to Clause 1, wherein the first polymerizable compound and the second polymerizable compound jointly form a copolymer skeleton.

[0087] Clause 3: The material according to Clause 2, wherein the second polymerizable compound includes polyester, poloxamer, polypropylene oxide, polyvinylpyrrolidone, poly(l-lactic acid), poly(lactic acid-co-glycolic acid), or a combination thereof.

[0088] Clause 4: The material described in Clause 2, wherein the volume ratio of the second polymerizable compound to the first polymerizable compound is in the range of approximately 0.125 to approximately 0.325.

[0089] Clause 5: The material described in Clause 1, which undergoes a phase transition from a swollen state to a disintegrated state when exposed to a temperature above a specified temperature.

[0090] Clause 6: The material according to Clause 5, wherein if the fluid has at least one of a temperature above a specified temperature and a pH above a specified pH, the first polymerizable compound and the second polymerizable compound decompose according to their respective first and second decomposition profiles.

[0091] Clause 7: The material described in Clause 1, wherein the specified temperature for the phase transition is in the range of approximately 25°C to approximately 35°C.

[0092] Clause 8: The material according to Clause 1, wherein a second polymerizable compound forms a coating around the first polymerizable compound, and as a result the coating prevents the first polymerizable compound from being exposed to fluid ingress over a predetermined period of time.

[0093] Clause 9: The material according to Clause 8, wherein the second polymerizable compound includes polymethacrylate, polydioxanone, polyanhydride, hydroxypropyl methylcellulose acetate succinate, cellulose acetate phthalate, cellulose acetate trimellitate, hydroxypropyl methylcellulose phthalate, polyvinyl acetate phthalate, poly(trimethylene carbonate), poly(beta-thioether ester ketal), polypropylene fumarate, poly(ester urea), poly(ester amide), or a combination thereof.

[0094] Clause 10: The materials described in Clause 8, wherein the specified period ranges from approximately 10 minutes to approximately 6 weeks.

[0095] Clause 11: The material described in Clause 8, wherein the coating has a thickness of approximately 20 μm to approximately 100 μm.

[0096] Clause 12: The material described in Clause 8, wherein the specified pH is in the range of approximately 6.5 to approximately 7.4.

[0097] Clause 13: The material described in Clause 1, wherein the material has a compressive strength of approximately 20 to approximately 70 kPa.

[0098] Clause 14: The material according to Clause 1, further comprising one or more medical additives configured to remain chemically bonded to at least one of the first polymerizable compound or the second polymerizable compound.

[0099] Clause 15: The material according to Clause 14, further configured such that one or more medical additives are released into the tissue over a predetermined period of time during at least one of the first and second degradation profiles.

[0100] Clause 16: A bioabsorbable material configured to be delivered to tissue, comprising a copolymer skeleton including a reaction product of a polyol and an isocyanate, a first polymerizable compound configured to degrade according to a first degradation profile, and a second polymerizable compound configured to degrade according to a second degradation profile different from the first degradation profile, wherein the material undergoes a phase transition in response to exposure to a fluid having a predetermined temperature.

[0101] Clause 17: The material according to Clause 16, wherein if the fluid has a temperature above a predetermined temperature, the first polymerizable compound and the second polymerizable compound decompose according to their respective first and second decomposition profiles.

[0102] Clause 18: A bioabsorbable material configured to be delivered to tissue, comprising a first polymerizable compound comprising a reaction product of a polyol and an isocyanate and configured to degrade according to a first degradation profile, and a second polymerizable compound for coating the first polymerizable compound, such that the coating prevents the first polymerizable compound from being exposed to fluid ingress over a predetermined period of time, wherein the material undergoes a phase transition in response to exposure to a fluid having a predetermined pH.

[0103] Clause 19: The material described in Clause 18, wherein the specified period is in the range of approximately 10 minutes to approximately 6 weeks, and the specified pH is in the range of approximately 6.5 to approximately 7.4.

[0104] Clause 20: The material described in Clause 18, wherein the coating has a thickness of approximately 20 μm to approximately 100 μm.

[0105] Clause 21: A bioabsorbable material configured to be delivered to tissue, comprising a reaction product of a polyol and an isocyanate, a first polymerizable compound configured to degrade according to a first degradation profile, and a second polymerizable compound configured to degrade according to a second degradation profile different from the first degradation profile, wherein the material undergoes a phase transition in response to exposure to a fluid having at least one of a predetermined temperature, an enzyme-catalyst, and a predetermined pH.

[0106] Clause 22: The material according to Clause 21, wherein the first polymerizable compound and the second polymerizable compound jointly form a copolymer skeleton.

[0107] Clause 23: The material according to Clause 21 or 22, wherein the second polymerizable compound comprises polyester, poloxamer, polypropylene oxide, polyvinylpyrrolidone, poly(l-lactic acid), poly(lactic acid-co-glycolic acid), or a combination thereof.

[0108] Clause 24: The material described in any one of Clauses 21 to 23, wherein the volume ratio of the second polymerizable compound to the first polymerizable compound is in the range of about 0.125 to about 0.325.

[0109] Clause 25: A material described in any one of Clauses 21 to 24, which undergoes a phase transition from a swollen state to a disintegrated state when exposed to a temperature above a specified temperature.

[0110] Clause 26: The material according to any one of Clauses 21 to 25, wherein the first polymerizable compound and the second polymerizable compound decompose according to their respective first and second decomposition profiles when the fluid has one or more of the following: a temperature above a specified temperature and a pH above a specified pH.

[0111] Clause 27: A material according to any one of Clauses 21 to 26, wherein the specified temperature of the phase transition is in the range of about 25°C to about 35°C.

[0112] Clause 28: The material according to Clause 21, wherein a second polymerizable compound forms a coating around the first polymerizable compound, and as a result the coating prevents the first polymerizable compound from being exposed to fluid ingress over a predetermined period of time.

[0113] Clause 29: The material according to Clause 28, wherein the second polymerizable compound includes polymethacrylate, polydioxanone, polyanhydride, hydroxypropyl methylcellulose acetate succinate, cellulose acetate phthalate, cellulose acetate trimellitate, hydroxypropyl methylcellulose phthalate, polyvinyl acetate phthalate, poly(trimethylene carbonate), poly(beta-thioether ester ketal), polypropylene fumarate, poly(ester urea), poly(ester amide), or a combination thereof.

[0114] Clause 30: Materials specified in any one of Clauses 28-29, wherein the specified period ranges from approximately 10 minutes to approximately 6 weeks.

[0115] Clause 31: A material according to any one of Clauses 28 to 30, wherein the second polymerizable compound has a thickness of about 20 μm to about 100 μm.

[0116] Clause 32: A material as described in any one of Clauses 28 to 31, wherein the specified pH is in the range of approximately 6.5 to approximately 7.4.

[0117] Clause 33: A material as described in any one of Clauses 21 to 32, wherein the material has a compressive strength of approximately 20 to approximately 70 kPa.

[0118] Clause 34: The material described in any one of Clauses 21 to 33, further comprising one or more medical additives configured to remain chemically bonded to one or both of the first polymerizable compound and the second polymerizable compound.

[0119] Clause 35: The material according to any one of Clauses 21 to 34, further configured to release one or more medical additives into the tissue over a predetermined period of time between one or both of the first and second degradation profiles.

[0120] [Implementation Method] (1) A bioabsorbable material configured to be delivered to tissue, A first polymerizable compound comprising a reaction product of a polyol and an isocyanate, configured to decompose according to a first decomposition profile, and A second polymerizable compound configured to decompose according to a second decomposition profile different from the first decomposition profile, A material that undergoes a phase transition in response to exposure to a fluid having at least one of a predetermined temperature, an enzyme-catalyst, and a predetermined pH. (2) The material according to Embodiment 1, wherein the first polymerizable compound and the second polymerizable compound jointly form a copolymer skeleton. (3) The material according to Embodiments 1 to 2, wherein the second polymerizable compound includes polyester, poloxamer, polypropylene oxide, polyvinylpyrrolidone, poly(l-lactic acid), poly(lactic acid-co-glycolic acid), or a combination thereof. (4) The material according to any one of Embodiments 1 to 3, wherein the volume ratio of the second polymerizable compound to the first polymerizable compound is in the range of about 0.125 to about 0.325. (5) The material according to any one of Embodiments 1 to 4, wherein the material undergoes a phase transition from a swollen state to a disintegrated state when exposed to a temperature exceeding the predetermined temperature.

[0121] (6) The material according to any one of embodiments 1 to 5, wherein when the fluid has one or more of the following: a temperature above the predetermined temperature and a pH above the predetermined pH, the first polymerizable compound and the second polymerizable compound decompose according to their respective first and second decomposition profiles. (7) The material according to any one of embodiments 1 to 6, wherein the predetermined temperature of the phase transition is in the range of about 25°C to about 35°C. (8) The material according to Embodiment 1, wherein the second polymerizable compound forms a coating around the first polymerizable compound, and as a result, the coating prevents the first polymerizable compound from being exposed to fluid ingress over a predetermined period of time. (9) The material according to Embodiment 8, wherein the second polymerizable compound includes polymethacrylate, polydioxanone, polyanhydride, hydroxypropyl methylcellulose acetate succinate, cellulose acetate phthalate, cellulose acetate trimellitate, hydroxypropyl methylcellulose phthalate, polyvinyl acetate phthalate, poly(trimethylene carbonate), poly(beta-thioether ester ketal), polypropylene fumarate, poly(ester urea), poly(ester amide), or a combination thereof. (10) The material according to Embodiment 8 or 9, wherein the predetermined period is in the range of about 10 minutes to about 6 weeks.

[0122] (11) The material according to any one of embodiments 8 to 10, wherein the second polymerizable compound has a thickness of about 20 μm to about 100 μm. (12) The material according to any one of embodiments 8 to 11, wherein the predetermined pH is in the range of about 6.5 to about 7.4. (13) The material according to any one of embodiments 1 to 12, wherein the material has a compressive strength of about 20 to about 70 kPa. (14) The material according to any one of embodiments 1 to 13, further comprising one or more medical additives configured to remain chemically bonded to one or both of the first polymerizable compound and the second polymerizable compound. (15) The material according to any one of embodiments 1 to 14, wherein one or more medical additives are further configured to be released into the tissue over a predetermined period of time between one or both of the first and second degradation profiles.

Claims

1. A bioabsorbable material configured to be delivered to tissue, A first polymerizable compound comprising a reaction product of a polyol and an isocyanate, configured to decompose according to a first decomposition profile, and A second polymerizable compound configured to decompose according to a second decomposition profile different from the first decomposition profile, A material that undergoes a phase transition in response to exposure to a fluid having at least one of a predetermined temperature, an enzyme-catalyst, and a predetermined pH.

2. The material according to claim 1, wherein the first polymerizable compound and the second polymerizable compound jointly form a copolymer skeleton.

3. The material according to claims 1 to 2, wherein the second polymerizable compound includes polyester, poloxamer, polypropylene oxide, polyvinylpyrrolidone, poly(l-lactic acid), poly(lactic acid-co-glycolic acid), or a combination thereof.

4. The material according to claim 1, wherein the volume ratio of the second polymerizable compound to the first polymerizable compound is in the range of about 0.125 to about 0.

325.

5. The material according to claim 1, wherein when the material is exposed to a temperature exceeding the predetermined temperature, it undergoes a phase transition from a swollen state to a disintegrated state.

6. The material according to claim 1, wherein if the fluid has one or more of the following: a temperature exceeding the predetermined temperature and a pH exceeding the predetermined pH, the first polymerizable compound and the second polymerizable compound decompose according to their respective first and second decomposition profiles.

7. The material according to claim 1, wherein the predetermined temperature of the phase transition is in the range of about 25°C to about 35°C.

8. The material according to claim 1, wherein the second polymerizable compound forms a coating around the first polymerizable compound, and as a result, the coating prevents the first polymerizable compound from being exposed to fluid ingress over a predetermined period of time.

9. The material according to claim 8, wherein the second polymerizable compound includes polymethacrylate, polydioxanone, polyanhydride, hydroxypropyl methylcellulose acetate succinate, cellulose acetate phthalate, cellulose acetate trimellitate, hydroxypropyl methylcellulose phthalate, polyvinyl acetate phthalate, poly(trimethylene carbonate), poly(beta-thioether ester ketal), polypropylene fumarate, poly(ester urea), poly(ester amide), or a combination thereof.

10. The material according to claim 8 or 9, wherein the predetermined period is in the range of approximately 10 minutes to approximately 6 weeks.

11. The material according to claim 8, wherein the second polymerizable compound has a thickness of about 20 μm to about 100 μm.

12. The material according to claim 8, wherein the predetermined pH is in the range of about 6.5 to about 7.

4.

13. The material according to claim 1, wherein the material has a compressive strength of about 20 to about 70 kPa.

14. The material according to claim 1, further comprising one or more medical additives configured to remain chemically bonded to one or both of the first polymerizable compound and the second polymerizable compound.

15. The material according to claim 1, wherein one or more medical additives are further configured to be released into the tissue over a predetermined period of time between one or both of the first and second degradation profiles.

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