A laser printing method for interbody fusion devices

Abstract

This invention discloses a laser printing method for interbody fusion devices and an interbody fusion device, relating to the field of medical devices. The laser printing method for the interbody fusion device includes: establishing a printing model comprising an intermediate model, an interbody fusion device model, and a dummy connection layer; establishing laser printing parameters based on the printing model, wherein the energy density of the laser input corresponding to the dummy connection layer differs from the energy density corresponding to the intermediate model and the interbody fusion device model; printing according to the laser printing parameters to obtain a printed structure; applying a force to destroy the dummy connection between each interbody fusion device and the intermediate model to remove the intermediate model, thereby obtaining multiple interbody fusion devices. The laser printing method for the interbody fusion device provided by this invention can significantly improve the fabrication efficiency of the interbody fusion device and reduce the fabrication cost.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and more specifically, to a laser printing method for an interbody fusion device and the interbody fusion device itself. Background Technology

[0002] Currently, metal laser powder bed 3D printing technology is the most widely used metal 3D printing technology. Because of its small laser spot size, the printing process does not require preheating of the powder layer, and it can form products with higher resolution and surface accuracy and more complex structures.

[0003] When this printing technology is applied to the fabrication of intervertebral fusion devices, the need to set up a relatively dense and high-strength support structure on the product makes it impossible to print in batches at one time. Furthermore, the subsequent product processing procedures are complex, which affects the fabrication efficiency and increases the fabrication cost. Summary of the Invention

[0004] The purpose of this invention is to provide a laser printing method for interbody fusion devices, which can significantly improve the preparation efficiency of interbody fusion devices and reduce the preparation cost.

[0005] Another objective of this invention is to provide an intervertebral fusion device that features high manufacturing efficiency and low manufacturing cost.

[0006] An embodiment of the present invention provides a technical solution:

[0007] A laser printing method for an interbody fusion device includes:

[0008] A printed model is established, comprising an intermediate model, an interbody fusion cage model, and a virtual connection layer. The multiple interbody fusion cage models are arranged sequentially at intervals in the vertical direction. The intermediate model is located between any two adjacent interbody fusion cage models. Any interbody fusion cage model and the intermediate model are connected through the virtual connection layer.

[0009] Laser printing parameters are established based on the printing model, wherein the energy density of the laser input corresponding to the virtual connection layer is different from the energy density corresponding to the intermediate model and the intervertebral fusion device model;

[0010] Printing is performed according to the laser printing parameters to obtain a printed structure, wherein the printed structure includes a plurality of intervertebral fusion devices arranged in sequence, and an intermediate body located between any two adjacent intervertebral fusion devices, and any intervertebral fusion device and the intermediate body are connected by a virtual connector.

[0011] A force is applied to destroy the dummy connection between each of the interbody fusion devices and the intermediate body, thereby removing the intermediate body and obtaining multiple interbody fusion devices.

[0012] In an optional embodiment, the interbody fusion cage model has a porous structure, and the pore size of the porous structure is normally distributed between 100 μm and 800 μm, and / or,

[0013] The porosity of the porous structure is greater than 40%.

[0014] In an optional embodiment, the porous structure is a regular structure or a disordered structure.

[0015] In an optional embodiment, each of the interbody fusion models has a downwardly protruding angled portion at its bottom end, and the surface of the upper corresponding angled portion of one of two adjacent interbody fusion models is covered by the dummy connection layer, and the angled portion is connected to the corresponding intermediate model through the dummy connection layer.

[0016] In an optional embodiment, the printed model further includes a support model that supports the intervertebral fusion device model at the bottom of the arrangement on the printed substrate. The angled portion of the intervertebral fusion device model at the bottom is connected to the support model through a dummy connection layer.

[0017] In an optional embodiment, each of the intervertebral fusion device models has a vertically downward extending fitting sinkhole at its top end. The intermediate body model includes a fitting rod model and a support cap model connected to the top end of the fitting rod model. The bottom end of the fitting rod model is embedded in the fitting sinkhole, and the gap between the fitting rod model and the hole wall of the fitting sinkhole is filled by the dummy connection layer.

[0018] The upper surface of the support cap model has a cavity corresponding to the angle portion, the angle portion of the corresponding intervertebral fusion device model is embedded in the cavity, and the gap between the angle portion and the cavity wall is filled by the dummy connection layer.

[0019] In an optional embodiment, the bottom wall of the countersunk hole has an angular recess, and the bottom end of the fitting rod model has an angular protrusion, which is embedded in the angular recess.

[0020] In an optional implementation, the dummy connection layer has lower strength compared to the intermediate model and the interbody fusion cage model, and / or,

[0021] The thickness of the virtual connection layer is between 0.1 mm and 0.5 mm.

[0022] In an optional implementation, the step of printing according to the laser printing parameters to obtain the printed structure includes:

[0023] Heat monitoring is performed during the printing process to obtain heat distribution data;

[0024] The printing parameters are adjusted in real time based on the heat distribution data to maintain heat balance.

[0025] The present invention also provides an interbody fusion device, which is prepared according to the aforementioned laser printing method for interbody fusion devices, the laser printing method for the interbody fusion device comprising:

[0026] A printed model is established, comprising an intermediate model, an interbody fusion cage model, and a virtual connection layer. The multiple interbody fusion cage models are arranged sequentially at intervals in the vertical direction. The intermediate model is located between any two adjacent interbody fusion cage models. Any interbody fusion cage model and the intermediate model are connected through the virtual connection layer.

[0027] Laser printing parameters are established based on the printing model, wherein the energy density of the laser input corresponding to the virtual connection layer is different from the energy density corresponding to the intermediate model and the intervertebral fusion device model;

[0028] Printing is performed according to the laser printing parameters to obtain a printed structure, wherein the printed structure includes a plurality of intervertebral fusion devices arranged in sequence, and an intermediate body located between any two adjacent intervertebral fusion devices, and any intervertebral fusion device and the intermediate body are connected by a virtual connector.

[0029] A force is applied to destroy the dummy connection between each of the interbody fusion devices and the intermediate body, thereby removing the intermediate body and obtaining multiple interbody fusion devices.

[0030] Compared to existing technologies, the laser printing method for intervertebral fusion devices provided by this invention establishes a printing model composed of an intermediate model, an intervertebral fusion device model, and a dummy connection layer. The dummy connection layer is actually a low-strength connection structure formed by the laser heating of printing powder. Through combination with the intermediate model, it achieves a virtual connection between multiple intervertebral fusion device models. The intermediate model corresponds to the printed intermediate body, the intervertebral fusion device model corresponds to the printed intervertebral fusion device, and the dummy connection layer corresponds to the printed dummy connection body. In the completed printing structure, the dummy connection body has low strength, achieving a low-strength connection between the intermediate body and the intervertebral fusion device. Therefore, after printing, by applying force to destroy the dummy connection body structure, the intermediate body and the intervertebral fusion device can be easily separated, eliminating the need for complex separation operations. Therefore, the beneficial effects of the laser printing method provided by this invention include: significantly improving the preparation efficiency of intervertebral fusion devices and reducing preparation costs. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as limiting the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A flowchart illustrating a laser printing method for an interbody fusion device provided in an embodiment of the present invention;

[0033] Figure 2 for Figure 1 A partial structural diagram of the printed model obtained in step S101;

[0034] Figure 3 for Figure 2 Enlarged view of region A in the middle;

[0035] Figure 4 for Figure 2 Enlarged view of region B in the middle;

[0036] Figure 5 for Figure 1 Schematic diagram of the intermediate model;

[0037] Figure 6 for Figure 1 A partial structural diagram of the printed structure obtained in step S103.

[0038] Icons: 100 - Printed model; 110 - Intermediate body model; 111 - Fitting rod model; 112 - Support cap model; 113 - Angled protrusion; 120 - Interbody fusion device model; 121 - Angled section; 122 - Fitting countersunk hole; 123 - Angled recess; 130 - Virtual connection layer; 140 - Support model; 200 - Printed structure; 210 - Interbody fusion device; 220 - Intermediate body; 230 - Virtual connection body. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0040] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0041] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0042] In the description of this invention, it should be understood that the terms "upper," "lower," "inner," "outer," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used to facilitate the description of this invention and to simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0043] Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0044] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, terms such as "set" and "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0045] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0046] Example

[0047] This embodiment provides a laser printing method for an interbody fusion device, used to fabricate an interbody fusion device 210. Please refer to [link / reference]. Figure 1 , Figure 1 The diagram shown is a flowchart of one possible laser printing method, which may include:

[0048] Step S101: Establish a printed model 100 including an intermediate model 110, an intervertebral fusion device model 120, and a virtual connection layer 130.

[0049] Please refer to the following: Figure 2, Figure 3 and Figure 4 , Figure 2 The image shown is a partial structural diagram of the printed model 100. Figure 3 As shown Figure 2 Enlarged diagram of region A in the middle. Figure 4 As shown Figure 2 Enlarged schematic diagram of region B in the middle.

[0050] The printed model 100 contains multiple interbody fusion device models 120, which are arranged sequentially at intervals in the vertical direction. There is an intermediate model 110 between any two adjacent interbody fusion device models 120, and any interbody fusion device model 120 and the intermediate model 110 are connected by a virtual connection layer 130.

[0051] Understandably, the interbody fusion device model 120 in the subsequent printing model 100 is printed to obtain the interbody fusion device 210, the intermediate body model 110 is printed to obtain the intermediate body 220, and the virtual connection layer 130 is printed to obtain the virtual connection body 230. In other words, Figure 2 The structure of the printed model 100 shown is basically the same as that of the printed structure 200 obtained by subsequent printing.

[0052] Compared to the intermediate model 110 and the interbody fusion cage model 120, the dummy connection layer 130 has lower strength. In fact, there is a gap between the interbody fusion cage model 120 and the intermediate model 110, and the dummy connection layer 130 fills the gap to achieve a dummy connection between the interbody fusion cage model 120 and the intermediate model 110, that is, a connection with lower strength.

[0053] In this embodiment, the thickness of the dummy connection layer 130 is between 0.1 mm and 0.5 mm, that is, the gap width between the interbody fusion device model 120 and the intermediate model 110 is between 0.1 mm and 0.5 mm.

[0054] During subsequent printing, the printing powder in the gap between the intervertebral fusion cage model 120 and the intermediate model 110 melts and solidifies to a certain extent under the thermal influence of the laser, forming a virtual connector 230 to achieve a virtual connection between the intervertebral fusion cage model 120 and the intermediate model 110. This ensures that the printed structure 200 can be successfully stacked and printed. After printing, the intervertebral fusion cage 210 and the intermediate model 220 can be easily separated by destroying the virtual connector 230. In this embodiment, the virtual connector 230 and the intermediate model 220 can be either solid structures or porous mesh structures.

[0055] The interbody fusion cage model 120 has a porous structure with a pore size that is normally distributed between 100 μm and 800 μm, and the porosity of the porous structure is greater than 40%.

[0056] In practical applications, the proportion of porous structures on the intervertebral fusion cage model 120 can be adjusted according to the actual application conditions. Increasing its proportion can reduce heat accumulation during the printing process, reduce the participation of thermal stress, and improve printing quality.

[0057] Porous structures can be regular or disordered. In the case of disordered structures, the porous structure unit nodes can move randomly in the XYZ directions according to a set random rate, thereby obtaining a randomized biomimetic porous structure.

[0058] In practical applications, as the degree of disorder increases, the local stress value inside the solid structure obtained by subsequent printing of porous structures will decrease significantly under mechanical loading conditions. The decrease in local stress value can improve the safety threshold of mechanical failure of the structure and is beneficial to load-bearing capacity.

[0059] In this embodiment, each interbody fusion device model 120 has a downwardly protruding angle portion 121 at its bottom end. The surface of the upper angle portion 121 of two adjacent interbody fusion device models 120 is covered with a virtual connection layer 130. The angle portion 121 is connected to the corresponding intermediate model 110 through the virtual connection layer 130.

[0060] The printed model 100 also includes a support model 140, which supports the intervertebral fusion device model 120 at the bottom of the arrangement on the printed substrate. The angle portion 121 of the intervertebral fusion device model 120 at the bottom is connected to the support model 140 through a virtual connection layer 130.

[0061] The angle portion 121 is actually a vertically downward protruding structure with a smooth transition. Due to the setting of the angle portion 121, abrupt slicing sections are avoided in the subsequent printing process, which is conducive to the gradual transfer of heat, reduces thermal gradient and deformation, and can also reduce the depth of laser penetration, resulting in better print quality.

[0062] Please refer to the following: Figure 5 , Figure 5 The diagram shown is a structural schematic of intermediate model 110.

[0063] In this embodiment, each interbody fusion device model 120 has a vertically downward extending fitting sinkhole 122 at its top end. The intermediate body model 110 includes a fitting rod model 111 and a support cap model 112 connected to the top end of the fitting rod model 111. The bottom end of the fitting rod model 111 is embedded in the fitting sinkhole 122, and the gap between the fitting rod model 111 and the hole wall of the fitting sinkhole 122 is filled by the dummy connection layer 130.

[0064] The upper surface of the support cap model 112 has a cavity corresponding to the angle portion 121. The angle portion 121 of the corresponding intervertebral fusion device model 120 is embedded in the cavity, and the gap between the angle portion 121 and the cavity wall is filled by the dummy connection layer 130.

[0065] Similarly, to avoid abrupt changes in the slice cross-section and further improve printing quality, in this embodiment, the bottom wall of the countersunk hole 122 has an angled recess 123, and the bottom end of the fitting rod model 111 has an angled protrusion 113, which is embedded in the angled recess 123. Preferably, in this embodiment, the angled recess 123 is conical, and the corresponding angled protrusion 113 is also conical.

[0066] In fact, the support model 140 also has the same cavity structure as the support cap model 112. The angle portion 121 of the intervertebral fusion device model 120 at the bottom end is embedded in the cavity of the support model 140 and is connected to the cavity wall through the virtual connection layer 130.

[0067] Please continue reading. Figure 1 The laser printing method provided in this embodiment may further include:

[0068] Step S102: Establish laser printing parameters based on printing model 100.

[0069] The energy density of the laser input corresponding to the virtual connection layer 130 is different from the energy density corresponding to the intermediate model 110 and the intervertebral fusion device model 120.

[0070] Understandably, slicing and printing simulations are performed on the printing model 100, and the simulation results are analyzed to guide the setting of scanning strategies and other parameters, thus establishing laser printing parameters.

[0071] In this embodiment, the laser power is set between 0W and 450W, the scanning rate is between 100mm / s and 3000mm / s, the overlap distance is between 0.05mm and 0.2mm, the layer thickness is between 0.02mm and 0.1mm, and the filling strategy is strip, island, linear, etc.

[0072] In practical applications, to form a dummy connection 230 between the intermediate body 220 and the interbody fusion device 210, it is necessary to control the laser printing parameters of the printing powder in the gap between the interbody fusion device model 120 and the intermediate body model 110. These parameters may include laser power, scanning speed, overlap distance, layer thickness, and filling strategy, thereby altering the corresponding energy density. This results in a lower strength for the dummy connection 230 formed after the printing powder melts and solidifies, significantly lower than the strength between the intermediate body 220 and the interbody fusion device 210.

[0073] The strengths of the intermediate body 220 and the interbody fusion device 210 can be the same or different, which can be achieved by configuring the energy densities corresponding to the intermediate body model 110 and the interbody fusion device model 120 in the laser printing parameters.

[0074] Please continue reading. Figure 1 The laser printing method provided in this embodiment may further include:

[0075] Step S103: Print according to the laser printing parameters to obtain the printed structure 200.

[0076] Please refer to the following: Figure 6 , Figure 6 The diagram shown is a partial structural schematic of the printed structure 200.

[0077] The printed structure 200 corresponds to the structure of the printed model 100. The printed structure 200 includes a plurality of intervertebral fusion devices 210 arranged in sequence, and an intermediate body 220 located between any two adjacent intervertebral fusion devices 210. Any intervertebral fusion device 210 and the intermediate body 220 are connected by a virtual connector 230.

[0078] During the printing process, layers of evenly laid printing powder form a powder bed. A laser beam scans the powder bed according to the scanning speed and path corresponding to the laser printing parameters, melting the printing powder to form a molten pool. Each layer of molten printing powder cools and solidifies to form a solid structure. Then, a new layer of printing powder is laid on top, and the scanning process is repeated until the printed structure 200 corresponding to the printed model 100 is obtained.

[0079] To ensure the stability of the printing process and further improve print quality, in this embodiment, step S103 may further include the following sub-steps:

[0080] Heat monitoring is performed during the printing process to obtain heat distribution data;

[0081] The printing parameters are adjusted in real time based on heat distribution data to maintain heat balance.

[0082] Understandably, by monitoring the heat changes of different structures and layer heights during the printing process, the laser printing parameters, mainly the laser power, are dynamically adjusted to maintain the heat balance of different parts of the solid structure formed during printing, thereby preventing the printed structure from overheating and deforming, which would affect the stability of the printing process.

[0083] Please continue reading. Figure 1 The laser printing method provided in this embodiment may further include:

[0084] Step S104: Apply force to destroy the virtual connection 230 between each intervertebral fusion device 210 and the intermediate body 220, so as to remove the intermediate body 220 and obtain multiple intervertebral fusion devices 210.

[0085] After printing, the printed structure 200 is removed from the powder bed. During removal, the dummy connection 230 between the support body corresponding to the support model 140 and the bottom intervertebral fusion device 210 breaks under stress, and the remaining part containing multiple intervertebral fusion devices 210 and intermediate body 220 is successfully removed. By twisting the intervertebral fusion device 210 or the intermediate body 220, the dummy connection 230 between them breaks, thus separating the intervertebral fusion device 210 and the intermediate body 220, thereby obtaining multiple intervertebral fusion devices 210. The operation is convenient and quick.

[0086] In summary, the laser printing method for interbody fusion devices provided in this embodiment can significantly improve the fabrication efficiency of the interbody fusion device 210 and reduce the fabrication cost.

[0087] This embodiment also provides an interbody fusion device 210, which is prepared according to the aforementioned laser printing method for interbody fusion devices. Benefiting from the advantages of this laser printing method, the interbody fusion device 210 provided in this embodiment has the characteristics of higher preparation efficiency and lower preparation cost.

[0088] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A laser printing method for an interbody fusion device, characterized in that, include: A printed model (100) is established, comprising an intermediate body model (110), an interbody fusion cage model (120), and a virtual connection layer (130). Multiple interbody fusion cage models (120) are arranged vertically at intervals. An intermediate body model (110) is located between any two adjacent interbody fusion cage models (120), and any interbody fusion cage model (120) is connected to the intermediate body model (110) via the virtual connection layer (130). Each interbody fusion cage model (120) has a downwardly protruding angled portion (121) at its bottom end and a vertically downwardly extending fitting countersunk hole (122) at its top end. The surface of the upper corresponding angled portion (121) of any two adjacent interbody fusion cage models (120) is covered by the virtual connection layer (130). The intermediate body model (110) includes a fitting rod model (111) and a support connected to the top end of the fitting rod model (111). The cap model (112) has its bottom end embedded in the fitting countersunk hole (122), and the gap between the fitting rod model (111) and the hole wall of the fitting countersunk hole (122) is filled by the virtual connection layer (130); the upper surface of the supporting cap model (112) has a cavity corresponding to the angle portion (121), and the angle portion (121) of the corresponding intervertebral fusion device model (120) is embedded in the cavity, and in the... The gap between the angle portion (121) and the cavity wall is filled by the dummy connecting layer (130), and the angle portion (121) is connected to the corresponding intermediate model (110) through the dummy connecting layer (130); compared with the intermediate model (110) and the intervertebral fusion device model (120), the dummy connecting layer (130) has lower strength, and / or the thickness of the dummy connecting layer (130) is between 0.1 mm and 0.5 mm; Laser printing parameters are established based on the printing model (100), wherein the energy density of the laser input corresponding to the virtual connection layer (130) is different from the energy density corresponding to the intermediate model (110) and the intervertebral fusion device model (120); Printing is performed according to the laser printing parameters to obtain a printed structure (200), wherein the printed structure (200) includes a plurality of intervertebral fusion devices (210) arranged in sequence, and an intermediate body (220) located between any two adjacent intervertebral fusion devices (210), and any intervertebral fusion device (210) and the intermediate body (220) are connected by a virtual connector (230); A force is applied to break the dummy connection (230) between each of the interbody fusion devices (210) and the intermediate body (220) to remove the intermediate body (220) and obtain a plurality of the interbody fusion devices (210).

2. The laser printing method for the interbody fusion device according to claim 1, characterized in that, The interbody fusion cage model (120) has a porous structure, and the pore size of the porous structure is normally distributed between 100 μm and 800 μm, and / or, The porosity of the porous structure is greater than 40%.

3. The laser printing method for the interbody fusion device according to claim 2, characterized in that, The porous structure can be a regular structure or a disordered structure.

4. The laser printing method for the interbody fusion device according to claim 1, characterized in that, The printed model (100) also includes a support model (140), which supports the intervertebral fusion device model (120) at the bottom of the arrangement on the printed substrate. The angle portion (121) of the intervertebral fusion device model (120) at the bottom is connected to the support model (140) through a virtual connection layer (130).

5. The laser printing method for the interbody fusion device according to claim 1, characterized in that, The bottom wall of the recessed hole (122) has an angled recess (123), and the bottom end of the mating rod model (111) has an angled protrusion (113), which is embedded in the angled recess (123).

6. The laser printing method for the interbody fusion device according to claim 1, characterized in that, The step of printing according to the laser printing parameters to obtain the printed structure (200) includes: Heat monitoring is performed during the printing process to obtain heat distribution data; The printing parameters are adjusted in real time based on the heat distribution data to maintain heat balance.

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