Layered Thiessen polygonal porous structure construction method

Abstract

The invention provides a layered Thiessen polygonal porous structure construction method, and belongs to the technical field of digital model construction. The invention provides a layered Thiessen polygonal porous structure construction method. The method comprises the following operation steps: obtaining a shape model of a porous area of an artificial implant prosthesis / implant; constructing a porous printing area model; obtaining multi-hole printing area layering; seed points are taken from the layered surface of the porous printing area; constructing a Thiessen polygon linear framework; setting a wire diameter to obtain a Thiessen polygonal printing frame; boolean intersection operation is carried out on the Thiessen polygon printing frame and the shape model; printing frame data are input into 3D printing equipment; printing a finished product. According to the layered Thiessen polygonal porous structure construction method provided by the invention, the porous printing area model is layered, so that the controllability of seed point selection is realized, the aperture range and the aperture channel of the porous structure are convenient to control, and the shape regularity of the Thiessen polygonal porous structure is improved.

Description

Technical Field

[0001] This invention belongs to the field of digital model construction technology, specifically relating to a method for constructing a layered Thiessen polygon porous structure. Background Technology

[0002] Bone loss caused by trauma or surgery is called bone defect. Bone defects can easily affect a patient's recovery, and bone grafting is generally used to treat them. Because the human body's bone self-repair cycle is too long and its reconstructive capacity is limited, artificial implants are often chosen as the primary option for bone grafting.

[0003] Artificial implants should possess the characteristics of human bone (such as mechanical, biological, mass, transport, and microstructural geometry). Their internal structure is a key factor influencing tissue regeneration, including nutrient diffusion, cell adhesion, and matrix deposition. Clinically used artificial implants are often made of dense metal, whose modulus is much higher than that of autologous bone. During service, this can lead to stress shielding, accelerating fatigue failure at the interface between the implant and other tissues. Furthermore, the dense metal does not provide sufficient space for bone ingrowth and tissue growth. To facilitate cell penetration and nutrient diffusion, and to avoid failure due to excessive modulus differences, the apparent elastic modulus of the artificial implant is reduced to a level similar to that of human bone. This significantly reduces the impact of stress shielding. Therefore, artificial implants often have a porous structure on their surface or inside. Common artificial implants include acetabular cups, femoral prostheses, tibial prostheses, interbody fusion cages, and knee prostheses. Depending on the site of application, porous structures can be placed on the surface of the implant, inside the implant, or extend from the surface into the implant. The implant can also be entirely composed of porous structures. A well-designed porous structure on the surface of the implant can promote the adhesion and proliferation of bone cells on the scaffold, achieving bio-fixation between the host bone and the implant.

[0004] 3D printing technology, a type of additive manufacturing, is a manufacturing technology that uses the geometric information of a digital CAD model as a basis. Through computer and CNC mechanical systems, it deposits metallic, non-metallic, and composite materials layer by layer using methods such as extrusion, sintering, melting, photopolymerization, and spraying to create physical objects. 3D printing technology expands the freedom between design and manufacturing through discrete-addition forming and material accumulation methods, making it possible to create integrated molding of complex structural parts and mass-produced personalized customization. Due to its technological characteristics, 3D printing technology is widely used in the production of artificial implants and prostheses.

[0005] When using 3D printing technology to produce artificial implants, the density and size of the pores in the artificial implants are uneven, the porous structure has an irregular shape, the pore diameter varies greatly, and the pore diameter range is large. It is easy for the pore diameter to be too large or too small. If the pore diameter is too small, it will seriously affect the growth and adhesion of cells, and the cells may have difficulty migrating into the artificial implant. If the pore diameter is too large, it will affect the lifespan of the implant. Summary of the Invention

[0006] The purpose of this invention is to provide a method for constructing a layered Tyson polygonal porous structure, which aims to solve the problems of excessively large pore size range, irregular shape, and large variation in pore size channels in the porous structure of artificial implants.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is: to provide a method for constructing a layered Thiessen polygonal porous structure, comprising the following steps: S1. Obtain the shape model of the porous region of the artificial implant / prosthesis; S2. Construct a model of the porous printing area to be printed in the computational space; S3. Divide the porous printing area model into layers to obtain the porous printing area layers; S4. Select seed points at the surface of the layered multi-hole printing area; S5. Combine the layers of the porous printing area to obtain a set of seed points for the porous printing area model; S6. Construct a linear framework of the Thiessen polygon based on the seed points of the obtained porous printing area model. S7. Based on the Thiessen polygon linear frame, the wire diameter is set to obtain the Thiessen polygon printing frame. S8. Perform Boolean intersection operation on the shape model of the Tyson polygon printing frame and the porous region of the artificial implant / implant to obtain the printing frame model data of the porous region of the artificial implant / implant to be printed. S9. Input the data of the printed frame model of the porous area of ​​the artificial implant / prosthesis into the 3D printing equipment; S10. Print the shape model of the porous region of the artificial implant / prosthesis.

[0008] In one possible implementation, in step S3, the thickness of the porous printing region layer is between 0.65 and 0.9 mm, and the thickness of the porous printing region layer matches the pore size of the porous structure.

[0009] In one possible implementation, in step S3, the distance between the opposite sidewalls of the porous printing region layer remains unchanged.

[0010] In one possible implementation, in step S4, the seed point of the surface of the first group of porous printing area layers that overlaps with the adjacent second group of porous printing area layers is located at the same position.

[0011] In one possible implementation, in step S4, the number of holes in the porous structure is adjusted by selecting the number of seed point positions on the surface of the porous printing area layer.

[0012] In one possible implementation, in step S4, the number of seed point locations is selected based on the number of seed points per unit area of ​​the surface layered in the porous printing region.

[0013] In one possible implementation, in step S4, the number of seed points per unit area on the surface of the porous printing area at different locations can be selected to be different.

[0014] In one possible implementation, in step S4, the number of seed points per unit area on the surface at different locations of the same set of porous printing regions can be selected to be different.

[0015] In one possible implementation, in step S4, some seed points selected at the surface of the porous printed area layer can be located on the surface of the shape model of the porous area of ​​the artificial implant / implant.

[0016] In one possible implementation, in step S7, the pore size of the porous structure is adjusted by selecting the width of the wire diameter and, in conjunction with the number of seed point positions selected at the surface of the porous printing area layer.

[0017] The beneficial effects of the layered Thiessen polygon porous structure construction method provided by this invention are as follows: Compared with the prior art, in step S1, the shape model of the porous area of ​​the artificial implant / implant to be implanted into the human body is first obtained. Patient CT data can be collected for personalized customization, or the shape model data of the pre-set porous area of ​​the artificial implant / implant can be collected for mass standardized production. It is applicable to a variety of situations and can be manufactured according to the actual situation. In step S2, data is calculated in the computing space, and a porous printing area model is constructed in the computing space. The size of each part of this porous printing area model is larger than the size of the artificial implant, that is, the artificial implant can be completely embedded in the porous printing area model, which facilitates the confirmation of the printing area of ​​the artificial implant in the later stage. In step S3, the porous printing region model is divided into multiple layers, each of which is a porous printing region layer. That is, the porous printing region model is obtained by stacking multiple groups of porous printing regions. Each group of porous printing regions is used as an individual for analysis. In step S4, the porous printing area has multiple circumferential surfaces in the layered structure. Seed points are selected on each surface of the porous printing area layer. The number of seed points is directly related to the number of holes formed on the porous printing area layer. The seed points are selected on the surface of the porous printing area layer, which is convenient for operation and limits the position of the seed points. The seed points are distributed on the same plane, which increases the regularity of the seed point distribution. The seed points are not arbitrarily distributed in the entire three-dimensional space. In step S5, the multiple groups of porous printing regions are divided and combined to restore the original porous printing region model. The seed points of all the porous printing regions are the set of seed points of the porous printing region model, and the set of the total number of seed points of the entire porous printing region model is obtained, which is convenient for subsequent calculation and printing. In step S6, Thiessen polygon calculation is performed on the seed points of the porous printing area model. The Thiessen polygon linear framework is constructed by spreading outward from the seed points in a circumferential direction. The Thiessen polygon linear framework has a high degree of compatibility with the porous structure and the distribution regularity of the seed points increases. Correspondingly, the regularity of the Thiessen polygon linear framework also increases. In step S7, the intersecting edges of the Thiessen polygons in the Thiessen polygon linear frame are the frame lines. By setting the wire diameter of the frame lines, the virtual Thiessen polygon linear frame can be converted into a solid Thiessen polygon printing frame. The wire diameter can be selected according to the actual situation so that the wire diameter meets the requirements of the porous structure of the artificial implant prosthesis. The Thiessen polygon printing frame is the solid porous structure that needs to be printed in 3D printing. The regularity of the Thiessen polygon linear frame increases, and correspondingly, the regularity of the resulting porous structure increases. In step S8, the shape model of the porous region of the artificial implant / implant can be completely embedded in the porous printing region model. The intersection of the shape model of the porous region of the artificial implant / implant and the shape model of the Thiessen polygon printing frame is selected, that is, Boolean intersection operation is performed on the two to obtain the Thiessen polygon linear frame of the shape model of the porous region of the artificial implant / implant, and the printing frame model data of the porous structure of the shape model of the porous region of the artificial implant / implant is obtained. In step S9, the printed frame model data of the artificial implant is input into the 3D printing equipment to provide printing data for the 3D printing equipment; In step S10, the 3D printing equipment prints the artificial implant prosthesis according to the input printing data; This method divides the porous printing region model into layers and selects seed points on the surface of the resulting porous printing region layers. The selection of seed point positions is limited to the surface. There are no seed points inside the porous printing region layers. In the thickness direction of the porous printing region layers, the distance between the seed points on the first end face and the seed points on the second end face of the porous printing region layers is fixed. In this case, by adjusting the thickness of the porous printing region layers, the distance between the seed points on the first end face and the seed points on the second end face of the porous printing region layers can be controlled, thereby adjusting the size of the formed Thiessen polygon and realizing the control of the pore size of the porous structure obtained by the Thiessen polygon linear frame. In the thickness direction of the porous printing region layer, when seed points are selected on the first end face and the second end face of the porous printing region layer, the relative positions of the seed points on the first end face and the second end face of the porous printing region layer can be controlled to adjust the relative positions of the Thiessen polygons formed by the first end face and the second end face of the porous printing region layer, thereby realizing the control of the pore size channel of the porous structure obtained by the linear frame of the Thiessen polygon. That is, in the thickness direction of the layering of the porous printing area, the selection of seed points of the porous printing area model is regular. The regularity of the Thiessen polygon linear framework built based on the seed points increases, and the regularity of the porous structure obtained by the Thiessen polygon linear framework increases synchronously. This method greatly improves the controllability of seed point selection, helps to control the pore size range and pore channels of porous structures, enhances the regularity of porous structures, avoids the phenomenon of pore size being too small or too large, avoids mutation of pore channels, promotes cell growth and adhesion, facilitates cell migration into artificial implants, prolongs the lifespan of artificial implants, and shortens the patient's recovery time. This method can be used to print a variety of 3D products and is compatible with various types of 3D printing equipment, making it highly versatile. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1This is a schematic diagram corresponding to operation step S2 of the method for constructing a layered Thiessen polygonal porous structure provided in an embodiment of the present invention. Figure 2 This is a schematic diagram corresponding to operation step S3 of the method for constructing a layered Thiessen polygonal porous structure provided in an embodiment of the present invention. Figure 3 This is a schematic diagram corresponding to operation step S4 of the method for constructing a layered Thiessen polygonal porous structure provided in Embodiment 1 of the present invention. Figure 4 This is a schematic diagram corresponding to operation step S4 of the method for constructing a layered Thiessen polygonal porous structure provided in Embodiment 2 of the present invention. Figure 5 This is a schematic diagram of operation step S6 in the method for constructing a layered Thiessen polygonal porous structure according to Embodiment 3 of the present invention. Figure 6 for Figure 5 A frontal view diagram; Figure 7 for Figure 5 A top-down view; Figure 8 for Figure 5 A schematic diagram of the Thiessen polygonal linear frame; Figure 9 To Figure 5 A schematic diagram of the containment setting of the Thiessen polygon linear frame; Figure 10 This is a multi-view schematic diagram of the porous structure of the layered Thiessen polygon porous structure construction method provided in Embodiment 4 of the present invention; Figure 11 This is a multi-view schematic diagram of the porous structure of the layered Thiessen polygon porous structure construction method provided in Embodiment 5 of the present invention; Figure 12 This is a multi-view schematic diagram of porous structures in the prior art. Detailed Implementation

[0020] To make the technical problems, solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0021] Please refer to Figures 1 to 11 The following describes a specific embodiment of a layered Thiessen polygon porous structure construction method provided by the present invention, including the following operation steps: S1. Obtain the shape model of the porous region of the artificial implant / prosthesis; S2. Construct a model of the porous printing area to be printed in the computational space; S3. Divide the porous printing area model into layers to obtain the porous printing area layers; S4. Select seed points at the surface of the layered multi-hole printing area; S5. Combine the layers of the porous printing area to obtain a set of seed points for the porous printing area model; S6. Construct a linear framework of the Thiessen polygon based on the seed points of the obtained porous printing area model. S7. Based on the Thiessen polygon linear frame, the wire diameter is set to obtain the Thiessen polygon printing frame. S8. Perform Boolean intersection operation on the shape model of the Tyson polygon printing frame and the porous region of the artificial implant / implant to obtain the printing frame model data of the porous region of the artificial implant / implant to be printed. S9. Input the data of the printed frame model of the porous area of ​​the artificial implant / prosthesis into the 3D printing equipment; S10. Print the porous area of ​​the artificial implant / prosthesis.

[0022] As a specific implementation of the layered Thiessen polygon porous structure construction method provided by the present invention, S1, obtain the shape model of the porous region of the artificial implant / implant.

[0023] For details, please refer to Figures 1 to 11 The model building system is installed in a computer and is used to build shape models of porous areas of artificial implants / prostheses. By inputting relevant data into the model building system, the model can be built. The model building system is connected to a 3D printing device to transmit the model data to the 3D printing device for printing.

[0024] Obtain the shape model of the artificial implant to be implanted in the human body. For patients with personalized product customization needs, the patient's CT data can be collected and uploaded to the model building system to build a shape model of the artificial implant that conforms to the patient's own characteristics.

[0025] Among common artificial implants, some implants, such as interbody fusion devices and knee joint prostheses, are mass-producible. For mass production, the shape model data of the porous area of ​​the implant is uploaded to the model building system according to the different models and specifications of the 3D printed products, so as to carry out mass production of the corresponding models and specifications of 3D printed products.

[0026] The present invention provides a method for constructing a layered Thésen polygonal porous structure, which is applicable to a variety of situations, including both personalized customization and mass production.

[0027] As a specific embodiment of the layered Thiessen polygon porous structure construction method provided by the present invention, please refer to Figure 1 S2. Construct a model of the porous printing area to be printed in the computational space.

[0028] For details, please refer to Figure 1 The data is calculated in the computational space of the model building system. A porous printing area model is built in the computational space. Seed points are selected and Thiessen polygons are constructed in the porous printing area model. The surface of the artificial implant has a porous structure. In order to ensure the integrity of the porous structure on the surface of the artificial implant, the porous printing area model needs to completely encompass the area where the artificial implant is located.

[0029] The dimensions of each part of the porous printed area model are larger than the dimensions of the artificial implant. The length of the porous printed area model is greater than the maximum length of the artificial implant, the width of the porous printed area model is greater than the maximum width of the artificial implant, and the height of the porous printed area model is greater than the maximum height of the artificial implant. In other words, the artificial implant can be completely embedded in the porous printed area model, which facilitates the confirmation of the area for printing the artificial implant in the later stage.

[0030] The porous printing area model can be constructed in a cuboid shape. Figure 1 The cube in the model represents the porous printing region model constructed within the computational space. This facilitates the confirmation and input of data for the porous printing region model and allows for layering operations on the model.

[0031] Depending on the actual shape of the artificial implant to be printed, the porous printing area model can also be constructed into other shapes such as cubes, spheres, hemispheres, and combinations of hemispheres and cuboids.

[0032] As a specific embodiment of the layered Thiessen polygon porous structure construction method provided by the present invention, please refer to Figure 2 S3. Layer the porous printing area model to obtain porous printing area layers; the thickness of the porous printing area layers is between 0.65 and 0.9 mm, and the thickness of the porous printing area layers matches the pore diameter of the porous structure; the distance between the opposite side walls of the porous printing area layers remains unchanged.

[0033] For details, please refer to Figure 2Along a defined direction, the porous printing region model is divided into multiple layers, each layer being a porous printing region layer. The surface used to divide the porous printing region model into layers is called the layer. In other words, the porous printing region model is obtained by stacking multiple groups of porous printing regions. The surfaces of the porous printing regions obtained by the layering are called the first end face and the second end face. Each group of porous printing regions is used as an individual for analysis, and data analysis is performed.

[0034] Layers can be planar.

[0035] The porous printing area model can be layered along the height direction. The layers of the porous printing area model are horizontal, and the first and second end faces of each layer are parallel horizontal planes. Figure 2 This is the case in China. Figure 2 The multi-layered cube obtained in the process is the layered porous printing area after division.

[0036] The porous printing area model can be layered along its length. The layers of the porous printing area model are vertical, and the first and second end faces of the porous printing area layer are parallel vertical surfaces.

[0037] The porous printing area model can be layered along the width direction. The layers of the porous printing area model are vertical, and the first and second end faces of the porous printing area layer are parallel vertical surfaces.

[0038] The porous printing area model can be layered along a fixed tilt angle. The layers of the porous printing area model are tilted, and the first and second end faces of the porous printing area layer are parallel inclined surfaces.

[0039] Layers can also be curved surfaces or regularly varying curved surfaces.

[0040] As a specific embodiment of the layered Thiessen polygon porous structure construction method provided by the present invention, please refer to Figure 3 , Figure 4S4. Seed points are selected at the surface of the porous printing area layers; the seed point selection positions of the surfaces of the first group of porous printing area layers and the adjacent second group of porous printing area layers are consistent; the number of pore positions of the porous structure is adjusted by selecting the number of seed point positions at the surface of the porous printing area layers; the number of seed point positions is selected according to the number of seed points per unit area of ​​the surface of the porous printing area layers; the number of seed points per unit area of ​​the surface of the porous printing area layers at different locations can be selected to be different; the number of seed points per unit area of ​​the surface at different locations of the same group of porous printing area layers can be selected to be different; some of the seed points selected at the surface of the porous printing area layers can be located on the surface of the shape model of the porous area of ​​the artificial implant / implant.

[0041] For details, please refer to Figure 3 , Figure 4 The outer side of the porous printing region layer has multiple surfaces. Taking a cuboid porous printing region layer as an example, seed points are selected on all six surfaces of the porous printing region layer. Figure 3 , Figure 4 The point set at the surface of the layered area in the multi-hole printing region is the selected seed point. Figure 3 , Figure 4 Two different seed point selection embodiments are given. The number of seed point positions is directly related to the number of holes formed on the porous printing area layer. The construction of the Thiessen polygon is carried out from the seed point in the circumferential direction until it comes into contact with the Thiessen polygons obtained by diffusion from other seed points. The final Thiessen polygon is the position of the holes in the porous structure.

[0042] Seed points are selected on the layered surface of the porous printing area for ease of operation, and the position of the seed points is limited. The seed points are distributed on the same plane, increasing the regularity of the seed point distribution. The seed points are not arbitrarily distributed throughout the entire three-dimensional space. The position of the Thiessen polygons obtained by the diffusion of the seed points is also limited. The Thiessen polygons diffuse outward from the layered surface of the porous printing area, increasing the regularity of the Thiessen polygon distribution. The Thiessen polygons are distributed along the layered surface of the porous printing area.

[0043] Seed points are selected at the surface of the porous printing area layer. Two adjacent sets of porous printing area layers have overlapping end faces. On these overlapping end faces, the seed point selection positions of the two adjacent sets of porous printing area layers are consistent. That is, the layering surface is used to layer the porous printing area model, and the seed point is selected on the layering surface.

[0044] The position of the seed point is the position of the Thiessen polygon. By adjusting the number of seed points, the number of Thiessen polygons can be adjusted. When the number of seed points increases within a unit area, the number of Thiessen polygons increases, the number of holes in the porous structure increases, the side length of the Thiessen polygons decreases, and the aperture of the porous structure obtained from the Thiessen polygons decreases. By adjusting the number of seed points, the number and aperture of the holes in the porous structure can be adjusted.

[0045] Determine the specific number of seed points per unit area, distribute the specified number of seed points on the layered surface of the porous printing area, and the seed points diffuse to obtain a specified number of Thiessen polygons, that is, to obtain a specified number of pores in the porous structure.

[0046] Seed points can be evenly distributed on the surface of the porous printing area, resulting in a more regular distribution of Thiessen polygons, which helps to improve the uniformity of the pore distribution in the porous structure.

[0047] Seed points are distributed unevenly on a set of surfaces in a layered porous printing area, with different distribution densities on the surface, which can realize the printing of porous structures with variable gradients, making them more in line with the force exerted by the human body.

[0048] The seed points on the layered surface of the porous printing area at different locations can have different distribution densities. The pore size of the porous structure changes with the distribution density of the seed points, so that the pores of the porous structure have a distribution gradient that conforms to the physiological structure of the human body.

[0049] The seed points on the first and second end faces of the same group of porous printing areas can have different distribution densities. The pore size of the porous structure changes with the distribution density of the seed points, so that the pores of the porous structure have a distribution gradient that conforms to the physiological structure of the human body.

[0050] The seed points can have different distribution densities on the surface of the same group of porous printing areas as needed. The pore size of the porous structure changes with the distribution density of the seed points, so that the pores of the porous structure have a distribution gradient that conforms to the physiological structure of the human body.

[0051] When selecting seed points, the seed points can be located on the surface of the shape model of the porous region of the artificial implant / implant. At the seed points located on the surface of the shape model of the porous region of the artificial implant / implant, a pore of the porous structure is formed, that is, the surface of the shape model of the porous region of the artificial implant / implant has pores, which helps to achieve bone ingrowth.

[0052] The thickness of the layers in the porous printing area can be selected according to different needs. The thickness value directly affects the size of the Thiessen polygon formed by the seed point. Adjusting the thickness value of the layers in the porous printing area makes the pores of the porous structure have a distribution gradient that conforms to the physiological structure of the human body.

[0053] This method divides the porous printing region model into layers and selects seed points on the surface of the resulting porous printing region layers. The selection of seed points is limited to the surface. There are no seed points inside the porous printing region layers. In the thickness direction of the porous printing region layers, the distance between the seed points on the first end face and the seed points on the second end face of the porous printing region layers is fixed. In this case, by adjusting the thickness of the porous printing region layers, the distance between the seed points on the first end face and the seed points on the second end face of the porous printing region layers can be controlled, thereby adjusting the size of the formed Thiessen polygon and realizing the control of the pore size of the porous structure obtained by the linear framework of the Thiessen polygon.

[0054] In the thickness direction of the porous printing region layer, when seed points are selected on the first end face and the second end face of the porous printing region layer, the relative positions of the seed points on the first end face and the second end face of the porous printing region layer can be controlled to adjust the relative positions of the Thiessen polygons formed by the first end face and the second end face of the porous printing region layer, thereby realizing the control of the pore size channels of the porous structure obtained by the linear framework of the Thiessen polygons.

[0055] That is, in the thickness direction of the porous printing region layer, the selection of seed points of the porous printing region model is regular. The regularity of the Thiessen polygon linear framework built based on the seed points increases, and the regularity of the porous structure obtained by the Thiessen polygon linear framework increases synchronously.

[0056] As a specific implementation of the layered Thésen polygon porous structure construction method provided by the present invention, S5, the porous printing area is layered and combined to obtain a set of seed points of the porous printing area model.

[0057] Specifically, the multiple groups of porous printing regions are recombined and merged to restore the original porous printing region model. The seed points of all the porous printing regions are the set of seed points of the porous printing region model. The overlapping seed points can be regarded as a group of seed points. The set of the total number of seed points of the entire porous printing region model is obtained, which is convenient for subsequent calculation and printing.

[0058] As a specific embodiment of the layered Thiessen polygon porous structure construction method provided by the present invention, please refer to Figures 5 to 8 S6. Construct a Thiessen polygon linear framework based on the seed points of the obtained porous printing area model.

[0059] For details, please refer to Figures 5 to 8 Thiessen polygons are calculated from the seed points of the porous printed area model. The polygons diffuse outwards from the seed points, resulting in multiple sets of Thiessen polygons from multiple seed points. During the diffusion process, the edges of these sets of Thiessen polygons come into contact, eventually reaching the limit position to obtain a linear framework of Thiessen polygons. Figures 5 to 7 The point in the middle is the seed point. Figures 5 to 8 The framework structure in the text is the Thiessen polygon linear framework. The Thiessen polygon linear framework has a high compatibility with porous structures. The distribution pattern of the Thiessen polygon is consistent with the distribution pattern of the seed points. The seed points are selected on the surface of the layered porous printing area. The distribution regularity of the seed points increases, and correspondingly, the regularity of the Thiessen polygon linear framework increases.

[0060] Please refer to Figure 9 The obtained Thiessen polygonal linear frame is enclosed by a containment structure. That is, based on the obtained Thiessen polygonal linear frame, the breaks in the porous structure on the outer surface of the Thiessen polygonal linear frame are connected to form a complete porous structure, thereby improving the porous mechanical properties.

[0061] in, Figure 9 In, constitute Figure 9 The four sub-figures are schematic diagrams of the Thiessen polygonal linear frame from different perspectives.

[0062] Please refer to Figure 10 , Figure 11 These are schematic diagrams of different embodiments of the Thiessen polygonal linear frame; constituting Figure 10 The four sub-figures are schematic diagrams from different perspectives of an embodiment of the Thiessen polygonal linear frame; constituting Figure 11 The four sub-figures are schematic diagrams from different perspectives of an embodiment of the Thiessen polygonal linear frame.

[0063] Figure 10 In this process, the seed points on the surface of the porous printing area at different locations can have different distribution densities. By changing the number of seed points on the surface of the porous printing area at different locations, gradient changes in the pore size, wire diameter, and porosity of the porous structure can be achieved.

[0064] Figure 11 In the process, the thickness of the layers in the porous printing area at different locations is different. By changing the thickness of the layers in the porous printing area at different locations, the gradient changes in the pore size, wire diameter, and porosity of the porous structure can be achieved.

[0065] As a specific embodiment of the layered Thiessen polygon porous structure construction method provided by the present invention, S7, based on the Thiessen polygon linear frame, the wire diameter is set to obtain the Thiessen polygon printing frame; by selecting the width of the wire diameter and in conjunction with the number of seed point positions selected at the layered surface of the porous printing area, the pore size of the porous structure is adjusted.

[0066] Specifically, the intersecting edges of the Thiessen polygons in the Thiessen polygon linear frame are the frame lines. By setting the wire diameter of the frame lines, the virtual Thiessen polygon linear frame can be converted into a solid Thiessen polygon printed frame. The wire diameter can be selected according to the actual situation so that the wire diameter meets the requirements of the porous structure of artificial implants.

[0067] If the wire diameter is too small, the strength of the implanted prosthesis will be too low, affecting the lifespan of the device. If the wire diameter is too large, the strength of the implanted prosthesis will be too high, which may cause stress shielding. At the same time, it may also cause the pore size of the porous structure to be too small, which is not conducive to bone ingrowth.

[0068] The Thiessen polygon printing frame is the porous structure that needs to be printed in 3D printing. As the regularity of the Thiessen polygon linear frame increases, the regularity of the resulting porous structure also increases.

[0069] As a specific implementation of the layered Thiessen polygon porous structure construction method provided by the present invention, S8, Boolean intersection operation is performed on the shape model of the Thiessen polygon printing frame and the porous region of the artificial implant / implant to obtain the printing frame model data of the porous region of the artificial implant / implant to be printed.

[0070] Specifically, the shape model of the porous region of the artificial implant / implant can be completely embedded within the porous printing region model. By selecting the intersection of the shape model of the porous region of the artificial implant / implant and the shape model of the Thiessen polygon printing frame, i.e., performing a Boolean intersection operation on the two, the Thiessen polygon linear frame of the shape model of the porous region of the artificial implant / implant can be obtained, thus obtaining the printing frame model data of the porous structure of the shape model of the porous region of the artificial implant / implant.

[0071] As a specific embodiment of the layered Tyson polygon porous structure construction method provided by the present invention, S9, the printing frame model data of the porous region of the artificial implant or implant is input into the 3D printing equipment.

[0072] Specifically, the data of the printed frame model of the artificial implant or the porous area of ​​the implant is input into the 3D printing equipment to provide printing data for the 3D printing equipment.

[0073] As a specific embodiment of the layered Tyson polygon porous structure construction method provided by the present invention, S10, printing the porous area of ​​the artificial implant or implant.

[0074] Specifically, the 3D printing equipment prints artificial implants or porous areas of implants based on the input printing data. This method can be used to print a variety of 3D printed products and is compatible with various types of 3D printing equipment, making it highly versatile.

[0075] Please refer to Figure 9 as well as Figure 12 ,in, Figure 12 In, constitute Figure 12 The four sub-figures are schematic diagrams of porous structures from different perspectives in the prior art. This method greatly improves the controllability of seed point selection, helps to control the pore size range and pore channels of porous structures, improves the regularity of porous structures, avoids the phenomenon of pore size being too small or too large, avoids the mutation of pore channels, promotes cell growth and adhesion, facilitates cell migration into artificial implants, prolongs the lifespan of artificial implants, and shortens the patient's recovery time.

[0076] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for constructing a layered Thiessen polygonal porous structure, characterized in that, The following steps are included: S1. Obtain the shape model of the porous region of the artificial implant / prosthesis; S2. Construct a model of the porous printing area to be printed in the computational space; S3. Divide the porous printing area model into layers to obtain the porous printing area layers; S4. Select seed points at the surface of the layered multi-hole printing area; S5. Combine the layers of the porous printing area to obtain a set of seed points for the porous printing area model; S6. Construct a linear framework of the Thiessen polygon based on the seed points of the obtained porous printing area model. S7. Based on the Thiessen polygon linear frame, the wire diameter is set to obtain the Thiessen polygon printing frame. S8. Perform Boolean intersection operation on the shape model of the Tyson polygon printing frame and the porous region of the artificial implant / implant to obtain the printing frame model data of the porous region of the artificial implant / implant to be printed. S9. Input the data of the printed frame model of the porous area of ​​the artificial implant / prosthesis into the 3D printing equipment; S10. Print the shape model of the porous region of the artificial implant / prosthesis.

2. The method for constructing a layered Thiessen polygonal porous structure as described in claim 1, characterized in that, In step S3, the thickness of the porous printing area layer is between 0.65 and 0.9 mm, and the thickness of the porous printing area layer matches the pore size of the porous structure.

3. The method for constructing a layered Thiessen polygonal porous structure as described in claim 1, characterized in that, In step S3, the distance between the opposite sidewalls of the porous printing area remains unchanged.

4. The method for constructing a layered Thiessen polygonal porous structure as described in claim 1, characterized in that, In step S4, the seed points of the overlapping surfaces of the first group of porous printing regions are located at the same positions.

5. The method for constructing a layered Thiessen polygonal porous structure as described in claim 1, characterized in that, In step S4, the number of holes in the porous structure is adjusted by selecting the number of seed point positions on the surface of the porous printing area layer.

6. The method for constructing a layered Thiessen polygonal porous structure as described in claim 1, characterized in that, In step S4, the number of seed point positions is selected based on the number of seed points per unit area of ​​the layered surface of the porous printing area.

7. The method for constructing a layered Thiessen polygonal porous structure as described in claim 6, characterized in that, In step S4, the number of seed points per unit area on the surface of the multi-hole printed area at different locations can be selected to be different.

8. The method for constructing a layered Thiessen polygonal porous structure as described in claim 6, characterized in that, In step S4, the number of seed points per unit area on the surface at different locations of the same group of porous printing areas can be selected to be different.

9. The method for constructing a layered Thiessen polygonal porous structure as described in claim 1, characterized in that, In step S4, some seed points selected at the surface of the porous printing area layer can be located on the surface of the shape model of the porous area of ​​the artificial implant / implant.

10. The method for constructing a layered Thiessen polygonal porous structure as described in claim 1, characterized in that, In step S7, the pore size of the porous structure is adjusted by selecting the width of the wire diameter and the number of seed points selected on the surface of the multi-hole printing area.

Images