Method for manufacturing a porous structure skull prosthesis based on 3D printing and injection molding technology

Abstract

The application discloses a porous structure skull prosthesis manufacturing method based on 3D printing and injection molding technology, relates to the technical field of skull defect repair prosthesis in neurosurgery, and comprises the following steps: performing three-dimensional reconstruction according to skull imaging data to obtain a skull three-dimensional model; manufacturing a male mold (also referred to as a convex mold) mold, a female mold (also referred to as a concave mold) mold and a porous sand structure according to the skull three-dimensional model; assembling the male mold mold, the female mold mold and the porous sand structure to be injection molded into a skull prosthesis model; and cooling, solidifying and sand cleaning the skull prosthesis model to obtain a skull repair prosthesis. The application is processed by means of CNC numerical control machining technology, injection molding technology and 3D printing technology, high-temperature injection molding is performed on a medical polymer material, and the skull repair prosthesis is obtained by removing the sand structure. The skull repair prosthesis can realize the ingrowth of scalp soft tissue, speeds up the skull repair and reconstruction process, and reduces the incidence of adverse reactions such as postoperative hydrops.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of neurosurgical skull repair technology, in particular to a porous structure skull prosthesis manufacturing method and device based on 3D printing and injection molding technology. BACKGROUND

[0002] The skull is one of the most important tissue organs of the human body. Due to surgical trauma or craniotomy treatment, skull defects are often left after craniocerebral surgery. If the diameter is 2-3 cm, the hard scar tissue can compensate for the weakness of the defect site, and generally no symptoms are produced. If the diameter is greater than 3 cm, the patient often has symptoms such as dizziness, headache, fear of noise, fear of shock, lack of stuffing in the defect site when standing, and swelling outside when the head is lowered. In order to meet the normal life needs of the patient, the patient's autologous free bone flap must be fixed, or an artificial repair prosthesis is used to repair the bone defect, so as to restore the original skull shape and anatomical structure, and is beneficial to preventing the occurrence of complications such as cerebrospinal fluid leakage and intracranial infection.

[0003] At present, the mainstream skull defect repair products on the market are titanium mesh plates and polyether ether ketone (PEEK) prostheses. The titanium mesh plate adopts a covering repair, and the thickness is less than 1 mm. According to the feedback of clinical adverse events research, there are cases of titanium mesh penetrating the scalp and titanium mesh depression and deformation under external force. At this time, the titanium mesh needs to be removed, and the prosthesis needs to be redesigned and implanted.

[0004] The PEEK skull prosthesis is a relatively high-end treatment scheme at present. Based on the three-dimensional reconstruction and prosthesis design of the patient's skull imaging data, the product is processed by high-precision CNC numerical control lathes, and the product adopts a three-dimensional embedded repair method and matches the skull defect area of the patient.

[0005] According to the feedback of clinicians, although the PEEK skull prosthesis has advantages such as chemical stability, excellent mechanical properties, and image compatibility, the PEEK skull prosthesis has the clinical problem of a much higher incidence of postoperative hydrops than the titanium mesh plate. The main reason is that the titanium mesh is a thin-walled porous structure, and the scalp soft tissue attached to the skull can climb and grow integrally. When the soft tissue grows successfully, the incidence of hydrocephalus can be reduced. The surface of the PEEK skull prosthesis is smooth, and the scalp soft tissue is difficult to climb. In addition, although the surface of the PEEK skull prosthesis is arranged with 2-4 mm through holes, the soft tissue only grows into the through holes to form a free "meat column", and cannot achieve multi-dimensional penetration, so it cannot achieve the close combination of soft tissue and skull, and reduce the supply of nutrients between cells in the soft tissue and skull tissue, thereby causing a high incidence of hydrocephalus.

[0006] In summary, in order to reduce the incidence of PEEK skull prosthesis cerebrospinal fluid adverse events, the basic principle is to achieve long-term stable fusion of skull tissue and attached soft tissue. The main method is to design a porous mesh structure on the skull prosthesis to facilitate tissue ingrowth.

[0007] The skull prosthesis with a porous mesh structure has implementation difficulties in the manufacturing process. Traditional CNC machining can only produce through-hole structures and cannot achieve the machining of a porous mesh structure. Although the additive manufacturing (3D printing) PEEK process technology is not limited by the structure design, it still has the problems of unstable process and substandard mechanical properties, and the clinical application still has high risks. SUMMARY

[0008] In order to solve the above problems existing in the prior art, the present application provides a porous structure skull prosthesis manufacturing method based on 3D printing and injection molding technology. This process combines the design freedom of 3D printing with the more stable injection molding process technology of industrial production, and can manufacture a porous mesh skull prosthesis with stable process and excellent mechanical properties, successfully achieving the fusion of skull tissue and attached soft tissue, so as to reduce the incidence of adverse events of cerebrospinal fluid after skull defect repair.

[0009] The technical scheme provided by the present application is as follows:

[0010] In a first aspect, the present application provides a porous structure skull prosthesis manufacturing method based on 3D printing and injection molding technology, which adopts the following technical scheme,

[0011] The porous structure skull prosthesis manufacturing method based on 3D printing and injection molding technology comprises:

[0012] Performing three-dimensional reconstruction on the basis of the skull imaging data to obtain a skull three-dimensional model;

[0013] Manufacturing a positive mold, a negative mold and a porous sand structure according to the skull three-dimensional model;

[0014] Assembling and injection molding the positive mold, the negative mold and the porous sand structure to obtain a skull prosthesis model;

[0015] Cooling and solidifying the skull prosthesis model to obtain a skull repair prosthesis.

[0016] As a further technical scheme of the present application, the skull three-dimensional model is obtained by performing three-dimensional reconstruction on the basis of the skull imaging data, specifically including: performing threshold segmentation, mirroring, stretching, porous design and center region porous structure design on the skull imaging data by Mimics and Freeform technology, and establishing a skull three-dimensional model.

[0017] As a further technical solution of the present application, the positive mold mold, the negative mold mold and the porous sand structure are prepared according to the skull three-dimensional model, and specifically include:

[0018] The curvature feature positive mold and the curvature feature negative mold of the skull three-dimensional model are obtained and processed to obtain positive mold data and negative mold data;

[0019] The positive mold mold and the negative mold mold are prepared according to the curvature feature positive mold and the curvature feature negative mold through a CNC numerical control machining method.

[0020] The porous sand structure is prepared according to the positive mold data and the negative mold data through a 3D printing coated sand technology.

[0021] As a further technical solution of the present application, the positive mold mold, the negative mold mold and the porous sand structure are prepared according to the skull three-dimensional model, and specifically include:

[0022] The positive mold mold, the negative mold mold and the porous sand structure are assembled, and the mold is installed on the mold frame of the injection molding machine;

[0023] The medical polymer material is injection molded to form the skull prosthesis model.

[0024] As a further technical solution of the present application, the medical polymer material is one of polyether ether ketone, polyether ketone ketone, polyaryletherketone, polymethyl methacrylate, polylactic acid and polyethylene.

[0025] As a further technical solution of the present application, the skull prosthesis model is cooled, solidified and cleaned to obtain a skull repair prosthesis, and specifically includes: the skull repair prosthesis includes an upper surface layer and a lower surface layer, the upper surface layer matches the curvature of the positive mold mold, the lower surface layer matches the curvature of the negative mold mold, and a connecting piece is arranged between the upper surface layer and the lower surface layer.

[0026] As a further technical solution of the present application, the skull repair prosthesis includes at least two layers of cell structures, the cell structure includes a cell, a cell connecting beam and a layer support beam, the cells are connected into a cell layer through the cell connecting beam, and the cell layers are connected into a multi-layer cell structure through the layer support beam.

[0027] As a further technical solution of the present application, the skull repair prosthesis further provides a reserved outer frame.

[0028] As a further technical solution of the present application, the negative mold mold is provided with a limiting groove and an injection hole, the positive mold mold is provided with a positioning pin hole and a first mounting hole, and the negative mold mold is provided with a positioning pin and a second mounting hole.

[0029] As a further technical solution of the present application, the porous sand structure is a porous sand structure made of coated sand.

[0030] The beneficial effects of the present application are:

[0031] The present application is processed by means of CNC numerical control machining technology, injection molding technology and 3D printing technology, wherein the CNC numerical control machining technology is used for the precise manufacturing of the male mold and the female mold of the skull repair prosthesis, the 3D printing technology is mainly used for the design and manufacturing of the porous sand structure in the middle region of the skull repair prosthesis, and the injection molding technology is used for the high-temperature injection molding of the medical polymer material after the assembly of the personalized mold and the porous structure mold. The polyether ether ketone skull defect prosthesis containing the porous sand structure is prepared by injection molding. After injection molding, the porous sand structure in the middle region of the skull prosthesis can be completely removed through different sand removal techniques, that is, the skull repair prosthesis with a certain pre-designed range of cavities can be obtained. The middle region of the porous skull prosthesis is a porous region, and compared with the traditional separated and arranged through-hole structure, the porous structure can realize the ingrowth of the scalp soft tissue, accelerate the blood supply and cell migration and climbing process, speed up the skull repair and reconstruction process, and reduce the incidence of adverse reactions such as postoperative hydrops. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 A porous structure skull prosthesis manufacturing method flow chart based on 3D printing and injection molding technology is provided for the present application;

[0033] Figure 2 A specific manufacturing method implementation flow chart of the porous structure skull prosthesis based on 3D printing and injection molding technology is provided for the present application;

[0034] Figure 3 A male mold structure diagram is provided for the present application;

[0035] Figure 4 A female mold structure diagram is provided for the present application;

[0036] Figure 5 A skull repair prosthesis structure diagram is provided for the present application;

[0037] Figure 6 A skull repair prosthesis local enlarged structure diagram is provided for the present application;

[0038] Figure 7 A sectional view of the combination of the male mold and the female mold is provided for the present application;

[0039] Figure 8 A structure diagram of a unit cell is provided for the present application;

[0040] Figure 9 Another structure diagram of a unit cell is provided for the present application;

[0041] The drawings show:

[0042] 1 - male mold, 2 - female mold, 3 - porous sand structure, 4 - skull repair prosthesis;

[0043] 101 - positioning pin hole, 102 - first mounting hole;

[0044] 201 - positioning pin, 202 - second mounting hole; 203 - limiting groove, 204 - injection hole;

[0045] 401 - upper surface layer, 402 - lower surface layer, 403 - connecting piece, 405 - unit cell structure, 406 - reserved outer frame;

[0046] 451 - unit cell, 452 - unit cell connecting beam, 453 - layer support beam. DETAILED DESCRIPTION

[0047] The concept, specific structure and technical effects of the present application will be described clearly and completely in combination with the embodiments and the drawings, so as to fully understand the purpose, features and effects of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all embodiments, and other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative labor are within the scope of protection of the present application.

[0048] As shown in the specific embodiments of the present application: Figures 1-9

[0049] Referring to Figure 1 , the present application provides a porous structure skull prosthesis manufacturing method based on 3D printing and injection molding technology, comprising:

[0050] In step 101, three-dimensional reconstruction is performed according to the skull imaging data to obtain a skull three-dimensional model;

[0051] In step 102, the male mold 1, the female mold 2 and the porous sand structure 3 are made according to the skull three-dimensional model;

[0052] In step 103, the male mold 1, the female mold 2 and the porous sand structure 3 are assembled and injection molded to form a skull prosthesis model;

[0053] In step 104, the skull prosthesis model is cooled, solidified and sand cleaned to obtain a skull repair prosthesis 4.

[0054] The present application combines 3D printing technology to realize the manufacturing of complex porous structure, and combines injection molding technology to realize the rapid and stable production required by industrial production. The manufactured porous skull defect repair prosthesis has reliable quality, can improve the postoperative soft tissue climbing property, can improve the bone integration of bone tissue, and can reduce the incidence of hydrocephalus after skull repair.

[0055] ​In step 101, the three-dimensional reconstruction is performed according to the cranial imaging data to obtain a cranial three-dimensional model; specifically, the cranial imaging data is subjected to threshold segmentation, mirroring, stretching, porous design and central region porous structure design through Mimics and Freeform technology to establish the cranial three-dimensional model. The designed model data file can be converted into STL format and the like.

[0056] The embodiment of the application is based on three-dimensional reconstruction of CT or MRI imaging data of a patient's skull. By means of medical modeling software (such as Mimics, Freeform and the like), through threshold segmentation, mirroring, stretching, porous design and other software functions, combined with the design requirements of a clinician for a skull prosthesis, the design of a personalized skull defect prosthesis and the design of a central region porous structure are realized, and the design of the skull prosthesis is collectively realized. The designed model data file can be converted into STL format and the like.

[0057] In step 102, the cranial three-dimensional model is used to manufacture a male mold, a female mold and a porous sand structure, specifically including:

[0058] The curvature feature male mold and the curvature feature female mold of the cranial three-dimensional model are obtained and processed to obtain male mold data and female mold data;

[0059] The male mold and the female mold are prepared by a CNC numerical control machining method according to the curvature feature male mold and the curvature feature female mold;

[0060] The porous sand structure is prepared by 3D printing film-coated sand technology according to the male mold data and the female mold data.

[0061] The male mold is also referred to as a convex mold, and the female mold is also referred to as a concave mold.

[0062] In step 103, the male mold, the female mold and the porous sand structure are assembled and injection molded to form a skull prosthesis model; specifically including:

[0063] The male mold, the female mold and the porous sand structure are assembled, and the mold is installed on the mold frame of an injection molding machine;

[0064] The skull prosthesis model is injection molded by using a medical polymer material.

[0065] The medical polymer material is one of polyether ether ketone, polyether ketone ketone, polyaryletherketone, polymethyl methacrylate, polylactic acid and polyethylene.

[0066] In the embodiment of the present application, the manufacturing of the skull repair prosthesis needs to simultaneously use CNC numerical control machining technology, injection molding technology and 3D printing technology, wherein the 3D printing technology is also called additive manufacturing. The CNC numerical control machining technology is mainly used for the precise manufacturing of the male mold and the female mold of the skull repair prosthesis, the 3D printing technology is mainly used for the design and manufacturing of the porous sand structure in the middle region of the skull repair prosthesis, and the injection molding technology is used for the high-temperature injection molding of the medical polymer material after the assembly of the personalized mold and the porous structure. The injection molding machine is started, polyether ether ketone (PEEK) particles are added, and the injection molding parameters are set, including temperature, pressure holding time, injection pressure, etc. The polyether ether ketone skull defect prosthesis containing the porous sand structure is prepared by injection molding. After injection molding, the porous sand structure in the middle region of the skull prosthesis can be completely removed by different sand cleaning technologies, and the skull repair prosthesis with a certain pre-designed range of cavities can be obtained.

[0067] In the embodiment of the present application, the porous sand structure 3 is a porous sand structure manufactured by coated sand.

[0068] In step 104, the skull prosthesis model is cooled and solidified to obtain the skull repair prosthesis 4, which specifically includes: the skull repair prosthesis 4 includes an upper surface layer 401 and a lower surface layer 402, the upper surface layer 401 matches the curvature of the male mold 1, the lower surface layer 402 matches the curvature of the female mold 2, and the upper surface layer 401 and the lower surface layer 402 are provided with a connecting piece 403.

[0069] The skull repair prosthesis 4 includes at least two layers of cell structures 405, the cell structure 405 includes a cell 451, a cell connecting beam 452 and a layer supporting beam 453, the cells 451 are connected into a cell layer through the cell connecting beam 452, and the cell layer is connected into a multi-layer cell structure through the layer supporting beam 453.

[0070] The complex porous structure is manufactured by 3D printing technology, the porous structure is formed by interlacing at least two layers of cell structures, and the upper surface layer and the lower surface layer of the porous structure skull prosthesis are supported and connected. The upper and lower surfaces of the porous structure are arc-shaped structures matching the physiological curvature of the skull.

[0071] In the embodiment of the present application, the skull repair prosthesis 4 is also provided with a reserved outer frame 406. The width of the reserved outer frame is 10-25 mm.

[0072] By setting the reserved outer frame, the porous skull prosthesis is fixed and linked with the original skull area of the patient by screws and link pieces in clinic, so as to achieve the purpose of matching repair. The middle region of the porous skull prosthesis is a porous region, and compared with the traditional separated and arranged through hole structure, the porous structure can realize the ingrowth of the scalp soft tissue, accelerate the blood supply and cell migration and climbing process, speed up the skull repair and reconstruction process, and reduce the incidence of adverse reactions such as postoperative hydrops.

[0073] In the embodiment of the application, the diameter of the cell connecting beam is 2-3 mm, and the porosity between the cells is 70%. The thickness of the multi-hole skull prosthesis is 4-6 mm. The diameter of the cell connecting beam is recommended to be 2-3 mm to ensure the expected support strength, and the porosity is recommended to be controlled at about 70%, as shown in the cell unit of Figure 8 The double-layer arrangement is recommended, and the connecting beam is arranged between the layers, as shown in the cell unit of Figure 9 The selection of the cell unit side length and the beam diameter should be based on the thickness of the skull prosthesis. Generally, the thickness of the porous skull prosthesis is preferably 4-6 mm.

[0074] The central region of the above-mentioned cell unit (typical representative structure one) adopts a sphere, and the connecting beams are arranged around the sphere. The number and arrangement direction of the connecting beams can be freely designed according to the curved surface structure of the individualized skull prosthesis. For example, as shown in Figure 2 The porous structure in the middle region is designed by using a spherical cell, and the connecting beams of the spherical cell are arranged only in the horizontal direction. The spherical cells are arranged in an upper and lower staggered arrangement, and the connecting beams are designed between the spherical cells of the two layers.

[0075] The above is a typical cell unit diagram of the "cage structure". The two sides of the cell unit adopt a polygonal design and are connected by a plurality of connecting beams.

[0076] The cell unit is arrayed, filled, and subjected to Boolean operation, etc., to cover the original intended porous design region, and form the intended designed porous structure. The upper surface layer and the lower surface layer of the porous structure are matched with the physiological curvature of the original skull of the patient, so as to achieve the effect of repair and beauty.

[0077] In the embodiment of the application, the female mold 2 is provided with a positioning pin 201 and a second mounting hole 202, the female mold 2 is provided with a limiting groove 203 and an injection hole 204, the male mold 1 is provided with a positioning pin hole 101 and a first mounting hole 102,

[0078] The positioning pin hole is designed on the edge of the male mold or the female mold, the positioning pin is arranged on the corresponding female mold or male mold, and the simple female mold and male mold are positioned by the positioning pin. The edge of the male mold and the female mold is designed with a threaded hole, and the male mold and the female mold are further fastened by the cooperation of the bolt and the nut, so that the female mold and the male mold are prevented from being separated or having a gap due to the too high injection pressure during injection molding, and the forming precision is affected.

[0079] In the embodiment of the application, in order to facilitate the placement and fixation of the porous structure manufactured by 3D printing between the female mold and the male mold, a protruding limiting groove is designed on the surface of the male mold or the female mold according to the size of the shape of the porous structure. The porous structure can be positioned through the limiting groove. After subsequent mold locking, the porous structure is further positioned and fixed, and subsequent displacement does not occur.

[0080] After the mold is locked, the molten raw material can be extruded into the mold through the injection hole to form the expected blank. The injection hole is designed on the front mold (close to the discharge direction of the screw). According to the actual mold clamping condition, the injection hole can be reasonably selected to be designed on the female mold or the male mold.

[0081] In the embodiment of the application, the original data of the personalized porous skull prosthesis is derived from the CT or MRI imaging data of the patient's skull. The medical modeling software is used, and the design requirements of the clinician for the skull prosthesis are combined to realize the design and shaping of the skull prosthesis.

[0082] The outer frame structure of the personalized male mold and female mold is wrapped and placed with a porous sand structure. The porous sand structure is a porous structure made of coated sand. When designing, a limiting groove for limiting the movement of the porous sand structure is designed on the female mold surface (which can also be designed on the male mold surface), the manufactured porous sand structure is embedded therein, and then the male mold is covered. After that, the mold is fixed by positioning pins and threads, and finally, the assembled body after mold fixing is placed on the mold frame of the injection molding machine. The equipment can be started, and the high-temperature molten medical polymer material is injected and filled into the outer frame and the porous sand structure in the middle area under the action of the screw push rod through the injection molding process.

[0083] The material for manufacturing the porous skull prosthesis is mainly medical polymer material such as polyether ether ketone (PEEK), polyether ketone ketone (PEKK), and polyaryletherketone (PAEK). Other materials such as polymethyl methacrylate (PMMA), polylactic acid (PLA), and polyethylene (PE) are also suitable for this process.

[0084] The mold material of the personalized male mold and female mold is mainly selected from different grades of aluminum, iron, steel and other mold materials.

[0085] The personalized multi-sand hole structure is mainly manufactured by 3D printing coated sand technology.

[0086] Under the manufacturing process, the personalized porous structure skull prosthesis expected to be manufactured is as shown in the figure. Figure 5 The product leaves a 10-25mm wide reserved outer frame at the edge, facilitating the fixation and linkage of the porous skull prosthesis and the original skull area of the patient with screws and link plates in the clinic, so as to achieve the purpose of matching repair. The middle area of the porous skull prosthesis is a porous area. Compared with the traditional separated and arranged through-hole structure, the porous structure can realize the ingrowth of the scalp soft tissue, accelerate the blood supply and cell migration and climbing process, speed up the skull repair and reconstruction process, and reduce the incidence of adverse reactions such as postoperative hydrops.

[0087] The porous structure of the middle area of the skull prosthesis needs to be considered in the design: the selection of the unit cell structure, the diameter of the unit cell connecting beam, the porosity formed after the unit cell array, and the unit cell arrangement mode of the inner and outer layers. The above factors will affect the performance of the final porous structure.

[0088] Through the previous research of the present application, it is suggested to select two typical representative unit cell structures as shown in Figure 8 and Figure 9 The diameter of the unit cell connecting beam is suggested to be 2-3mm to ensure the expected support strength, and the porosity is suggested to be controlled at about 70%. For the unit cell as shown in Figure 8 , it is suggested to select double-layer arrangement and set connecting beams between the layers. For the unit cell as shown in Figure 9 , the side length of the unit cell and the beam diameter should be selected according to the thickness of the skull prosthesis. Generally, the thickness of the porous skull prosthesis is preferably 4-6mm.

[0089] Figure 8 The central area of the unit cell as shown in Figure 9 adopts a spherical unit cell, and the connecting beams are arranged around the spherical unit cell. The number and arrangement direction of the connecting beams can be freely designed according to the curved surface structure of the personalized skull prosthesis. For example, as shown in , the middle area porous structure adopts a spherical unit cell design, and the connecting beams of the spherical unit cell are arranged only in the horizontal direction. The spherical unit cells are arranged in an upper and lower staggered arrangement, and connecting beams are designed between the spherical unit cells of the two layers.

[0090] Figure 9 The schematic diagram of a typical unit cell with a "cage structure" is shown in the figure. The two sides of the unit cell are designed as polygons and are connected by multiple connecting beams.

[0091] The unit cell is subjected to arraying, filling, Boolean operation and other processes to cover the original intended porous design area, forming the intended designed porous structure. The upper surface layer and the lower surface layer of the porous structure are matched with the physiological curvature of the original skull of the patient to achieve the effect of repair and beauty.

[0092] The application has been described in detail above, but the application is not limited to the above-mentioned embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the application. Many other changes and modifications can be made without departing from the concept and scope of the application. It should be understood that the application is not limited to the specific embodiments, and the scope of the application is defined by the appended claims.

Claims

1. A method for manufacturing a porous structure skull prosthesis based on 3D printing and injection molding technology, characterized in that, The application relates to a skull prosthesis manufacturing method. Three-dimensional reconstruction is performed according to skull image data to obtain a skull three-dimensional model; A positive mold, a negative mold and a porous sand structure are manufactured according to the skull three-dimensional model; The positive mold, the negative mold and the porous sand structure are assembled and injection molded to form a skull prosthesis model; The skull prosthesis model is cooled, solidified and cleaned to obtain a skull repair prosthesis. The manufacturing of the positive mold, the negative mold and the porous sand structure according to the skull three-dimensional model specifically comprises the following steps: Curvature characteristic positive molds and curvature characteristic negative molds of the skull three-dimensional model are obtained and processed to obtain positive mold data and negative mold data; The positive mold and the negative mold are manufactured through CNC numerical control machining according to the curvature characteristic positive molds and the curvature characteristic negative molds; The porous sand structure is manufactured through 3D printing and film-coated sand technology according to the positive mold data and the negative mold data; The positive mold, the negative mold and the porous sand structure are assembled and injection molded to form a skull prosthesis model. The three-dimensional reconstruction of the skull three-dimensional model according to the skull image data specifically comprises the following steps: The skull image data is subjected to threshold segmentation, mirroring, stretching, porous design and center region porous structure design through Mimics and Freeform technologies to establish the skull three-dimensional model.

2. The method of claim 1, wherein the method is a method of manufacturing a porous structure skull prosthesis based on 3D printing and injection molding technology, the method comprising: The medical polymer material is one of polyether ether ketone, polyether ketone ketone, polyaryletherketone, polymethyl methacrylate, polylactic acid and polyethylene.

3. The method of claim 1, wherein the method further comprises: The skull repair prosthesis comprises an upper surface layer and a lower surface layer, the upper surface layer is matched with the curvature of the positive mold, the lower surface layer is matched with the curvature of the negative mold, and a connecting piece is arranged between the upper surface layer and the lower surface layer.

4. The method of claim 1, wherein the method further comprises: The skull repair prosthesis comprises at least two layers of cell structures, the cell structure comprises a cell, a cell connecting beam and a layer support beam, the cells are connected into a cell layer through the cell connecting beam, and the cell layers are connected into a multi-layer cell structure through the layer support beam.

5. The method of claim 4, wherein the method further comprises: The skull repair prosthesis is further provided with a reserved outer frame.

6. The method of claim 4, wherein the method further comprises: The negative mold is provided with a limiting groove and an injection hole, the positive mold is provided with a positioning pin hole and a first mounting hole, and the negative mold is provided with a positioning pin and a second mounting hole.

7. The method of claim 1, wherein the method further comprises: 3D printing a porous structure skull prosthesis using a 3D printing technology; and injection molding the porous structure skull prosthesis using an injection molding technology. The porous sand structure is a porous sand structure manufactured by film-coated sand.

8. The method of claim 1, wherein the method further comprises: ​

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