Degradable porous metal net for repairing oral maxillofacial bone and preparation method of degradable porous metal net

Abstract

The invention discloses a degradable porous metal net for repairing oral and maxillofacial bones and a preparation method of the degradable porous metal net. The degradable porous metal net is provided with a film body made of degradable high-purity magnesium, and the film body is of a honeycomb-shaped through hole structure; the cross section of the honeycomb-shaped through hole structure is composed of a plurality of regular hexagons, any regular hexagon serves as a central regular hexagon, any adjacent regular hexagon and the central regular hexagon share one edge to be arranged, and the overall cross section of the honeycomb-shaped through hole structure is formed by sequentially and radially arranging the regular hexagons. The diameter of the inscribed circle of any regular hexagon is 0.5-1.2 mm, and the thickness of the hole wall between every two adjacent regular hexagons is 100-500 microns. The degradable porous metal net has the characteristics of being reasonable in structural design, excellent in mechanical property and controllable in degradation behavior, and the preparation process is high in precision and good in repeatability. The degradable porous metal net can be used for preparing guided bone regeneration medical instruments for maxillofacial surgery bone defect repair.

Description

Technical Field

[0001] This invention relates to the field of oral medicine technology, and in particular to a biodegradable porous metal mesh for oral and maxillofacial bone repair and its preparation method. Background Technology

[0002] Guided bone regeneration (GBR) is a core clinical approach for addressing insufficient bone volume in implantation sites and repairing bone defects caused by trauma, tumors, or inflammation. The key to its success lies in using a barrier membrane placed at the bone defect site. This membrane effectively blocks the ingrowth of rapidly migrating fibroblasts and epithelial cells into the defect area, thereby creating a relatively stable and undisturbed environment for the proliferation and differentiation of osteoblasts and blood vessels.

[0003] An ideal GBR barrier membrane should possess the following characteristics: good biocompatibility and biosafety; appropriate mechanical strength to resist soft tissue stress and maintain space for bone regeneration; controllable degradation performance, with a degradation cycle that matches the bone tissue regeneration cycle; and a porous structure that serves as a scaffold to promote bone ingrowth.

[0004] Currently, the GBR membranes widely used in clinical practice mainly include non-degradable membranes (such as titanium mesh and expanded polytetrafluoroethylene (e-PTFE) membranes) and degradable membranes (such as collagen membranes and polylactic acid membranes). Non-degradable membranes, especially titanium mesh, while providing excellent space maintenance capabilities, suffer from drawbacks such as high rigidity, difficulty in intraoperative shaping, easy exposure leading to infection, and the need for secondary surgery for removal, increasing patient suffering and financial burden. Degradable membranes, such as collagen membranes, avoid secondary surgery, but their mechanical strength is generally insufficient, making them difficult to effectively support complex bone defects. Furthermore, the degradation rate is difficult to control precisely, often resulting in premature loss of barrier function or long-term residue affecting bone healing.

[0005] In recent years, biodegradable metals, especially high-purity magnesium, have shown great potential in the field of biomedical materials due to their good biocompatibility, suitable mechanical properties, and degradability. High-purity magnesium also exhibits excellent biocompatibility, and the magnesium ions produced during degradation have been shown to significantly promote new bone formation.

[0006] However, applying biodegradable metals to GBR membranes still faces challenges: First, a simple dense metal film lacks the necessary porous structure, which is detrimental to nutrient transport and cell migration; second, an unreasonable pore design can easily lead to stress concentration points and corrosion initiation points in the interpore areas, resulting in premature structural failure; third, the matching of degradation behavior with the bone regeneration cycle still needs to be optimized through sophisticated structural design. Therefore, developing a biodegradable porous metal mesh for oral and maxillofacial bone repair that combines excellent mechanical support, controllable degradation rate, ideal porous structure, and effective bone regeneration guidance, as well as its preparation method, has become an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0007] One of the objectives of this invention is to overcome the shortcomings of the prior art and provide a biodegradable porous metal mesh for oral and maxillofacial bone repair and its preparation method. The biodegradable porous magnesium mesh has the characteristics of reasonable structural design, excellent mechanical properties and controllable degradation behavior.

[0008] The above-mentioned objectives of the present invention are achieved through the following technical measures.

[0009] A biodegradable porous metal mesh for oral and maxillofacial bone repair is provided, comprising a membrane body made of biodegradable metal, wherein the membrane body has a honeycomb-like through-pore structure; The cross-section of the honeycomb-shaped through-hole structure is composed of multiple regular hexagons. Any one of the regular hexagons is used as the central regular hexagon, and any adjacent regular hexagons share a side with the central regular hexagon. They are arranged radially in sequence to form the cross-section of the overall honeycomb-shaped through-hole structure. The diameter of the inscribed circle of any regular hexagon is 0.5-1.2 mm, and the wall thickness of the hole between adjacent regular hexagons is 100-500 μm.

[0010] Preferably, the biodegradable porous metal mesh for oral and maxillofacial bone repair described above has a membrane thickness of 0.3-2 mm.

[0011] Preferably, in the above-mentioned biodegradable porous metal mesh for oral and maxillofacial bone repair, the biodegradable metal is ultra-high purity magnesium or medical magnesium alloy or pure zinc or medical zinc alloy with a content of not less than 99.9 wt%.

[0012] Preferably, in the above-mentioned biodegradable porous metal mesh for oral and maxillofacial bone repair, the edge of the membrane body is provided with screw holes for fixation.

[0013] Preferably, in the above-mentioned biodegradable porous metal mesh for oral and maxillofacial bone repair, the diameter of the screw holes is 0.8-2.5 mm.

[0014] Another object of the present invention is to provide a method for preparing the above-mentioned biodegradable porous metal mesh for oral and maxillofacial bone repair, comprising the following steps: S1, 3D model design and wax model preparation, specifically: constructing a 3D digital model of a metal mesh, and then using 3D printing technology, using medical casting wax as the material, to print a wax model that is consistent with the shape of the final product; S2, embedding and dewaxing, specifically: placing the wax pattern inside the casting ring, embedding it with casting powder to form a mold; then baking and dewaxing are performed to obtain a ceramic mold with a honeycomb cavity; S3, Melting and Casting, specifically: under an argon protective atmosphere, the biodegradable metal raw material is melted, and after the metal is completely melted, it is poured into a preheated mold under an argon protective atmosphere.

[0015] S4, Cooling and Demolding: After pouring, allow the material to cool naturally to room temperature, remove the embedded material, and take out the metal mesh casting. S5, Post-processing: The casting is surface cleaned, machined, polished and cleaned to obtain the final biodegradable porous metal mesh.

[0016] Surface cleaning aims to remove oxide scale and embedded residue from the casting surface; machining aims to correct product dimensions, ensure screw hole accuracy and assembly compatibility; polishing aims to obtain a smooth, burr-free surface and avoid irritating oral tissues; cleaning aims to thoroughly remove machining residues and ensure biosafety.

[0017] Preferably, in the above method for preparing biodegradable porous metal mesh for oral and maxillofacial bone repair, the baking and dewaxing process in step S2 is as follows: the baking temperature is 80-120℃, and the temperature is maintained for 2-4 hours; then the temperature is raised to 380-450℃, and the temperature is maintained for 1-2 hours to complete the dewaxing.

[0018] Preferably, in the above method for preparing biodegradable porous metal mesh for oral and maxillofacial bone repair, S3 specifically involves melting at a melting temperature of 550-700°C for 30-60 minutes.

[0019] Preferably, in the above method for preparing biodegradable porous metal mesh for oral and maxillofacial bone repair, the preheating temperature of the mold in step S3 is 200-300℃, and the preheating holding time is 1-2 hours.

[0020] The present invention also provides the use of biodegradable porous metal mesh for oral and maxillofacial bone repair in the preparation of guided bone regeneration medical devices for repair of bone defects in maxillofacial surgery.

[0021] This invention relates to a biodegradable porous metal mesh for oral and maxillofacial bone repair and its preparation method. The biodegradable porous metal mesh for oral and maxillofacial bone repair comprises a membrane body made of biodegradable metal, wherein the membrane body has a honeycomb-like through-hole structure. The cross-section of the honeycomb-like through-hole structure is composed of multiple regular hexagons, with any one regular hexagon serving as the central regular hexagon. Adjacent regular hexagons share a side with the central regular hexagon and are arranged radially to form the cross-section of the overall honeycomb-like through-hole structure. The inscribed circle diameter of any one regular hexagon is 0.5-1.2 mm, and the wall thickness between adjacent regular hexagons is 100-500 μm.

[0022] The technical solution of the present invention has the following advantages: 1. A perfect combination of biomimetic structure and mechanical properties: Utilizing the optimal hexagonal honeycomb structure found in nature, this structure possesses the highest specific stiffness and specific strength in material mechanics. This invention miniaturizes it to the micrometer scale and applies it to a metal mesh. This allows the metal mesh to maintain a high porosity (typically >50%) to facilitate material exchange and cell migration, while possessing mechanical support capabilities far exceeding those of similar biodegradable polymer membranes. It can effectively resist soft tissue pressure within the oral cavity, providing a durable and stable space for bone regeneration.

[0023] 2. Optimized degradation behavior and biological function: (1) The use of biodegradable metals such as high-purity magnesium (99.9%) and ultra-high-purity magnesium (99.99%) or medical magnesium alloy or pure zinc or medical zinc alloy significantly reduces the accelerating effect of impurity elements on electrochemical corrosion, making the degradation rate more uniform and controllable, and the degradation product magnesium ions are known to be potent osteogenic promoting factors.

[0024] (2) The honeycomb structure distributes the degradation area evenly, avoiding the rapid fracture caused by stress concentration in the "narrow bridge" area between traditional round holes, making the degradation process more gradual and controllable, and the degradation cycle more easily matched with the 4-6 month bone regeneration cycle.

[0025] 3. Excellent biocompatibility and selective barrier function: The selected high-purity magnesium, ultra-high-purity magnesium, or medical-grade magnesium alloy, or pure zinc or medical-grade zinc alloy have excellent biocompatibility. The pore size (0.5-1.2mm) of the honeycomb cells is carefully designed to allow the free passage of body fluids, nutrients, and osteoblast-related cells, while effectively blocking the invasion of larger fibroblasts, achieving an ideal "selective barrier" function.

[0026] 4. Convenient Clinical Operation and Personalized Fit: The metal mesh possesses a certain degree of flexibility, allowing surgeons to precisely bend and shape it according to the bone defect during surgery. Pre-set fixing holes and matching screws at the edges ensure secure implant fixation, simplifying the operation. Combined with 3D printing wax model technology, rapid customization to the individual patient's bone defect morphology is possible, improving surgical fit and success rate.

[0027] 5. High-precision, repeatable advanced manufacturing process: The combined process of "3D printing wax pattern + precision embedding casting" is completed under argon protection, effectively preventing the oxidation of biodegradable metals. This process enables high-fidelity and high-consistency forming of complex biomimetic honeycomb structures, ensuring dense internal structure, few defects, and good batch stability of the castings, providing process assurance for the reliability of product mechanical properties and the predictability of degradation behavior. Attached Figure Description

[0028] The invention will be further described with reference to the accompanying drawings, but the contents of the drawings do not constitute any limitation on the invention.

[0029] Figure 1 This is a partial top view schematic diagram of a biodegradable porous metal mesh for oral and maxillofacial bone repair according to the present invention.

[0030] exist Figure 1 Including: Membrane body 100, regular hexagon 200, pore wall 300. Detailed Implementation

[0031] The present invention will be further described in conjunction with the following embodiments.

[0032] Example 1 A biodegradable porous metal mesh for oral and maxillofacial bone repair includes a membrane body 100 made of biodegradable metal. The membrane body 100 has a honeycomb-like porous structure, such as... Figure 1 As shown.

[0033] The cross-section of the honeycomb-shaped through-hole structure is composed of multiple regular hexagons 200. Any one of the regular hexagons 200 serves as the central hexagon, and adjacent regular hexagons share a side with the central hexagon, arranged radially in sequence to form the overall cross-section of the honeycomb-shaped through-hole structure. For example... Figure 1In the diagram, a regular hexagon A is the central hexagon, and six other regular hexagons are adjacent to A: B1, B2, B3, B4, B5, and B6. Each of B1, B2, B3, B4, B5, and B6 shares an edge with A. Similarly, a regular hexagon B6 is the central hexagon, and six other regular hexagons are adjacent to B6: B1, A, B5, C1, C2, and C3. Each of B1, A, B5, C1, C2, and C3 shares an edge with B6. The cross-sections of the honeycomb-like perforated structure are arranged radially to form the whole.

[0034] The diameter of the inscribed circle of any regular hexagon 200 is 0.5-1.2 mm, and the thickness of the hole wall 300 between adjacent regular hexagons 200 is 100-500 μm.

[0035] This biodegradable porous metal mesh for oral and maxillofacial bone repair has an overall membrane structure, with a membrane body 100 thickness of 0.3-2 mm. The membrane body 100 has screw holes (not shown in the figure) at its edges for fixation. The diameter of the screw holes is 0.8-2.5 mm.

[0036] This biodegradable porous metal mesh for oral and maxillofacial bone repair uses ultra-high purity magnesium, medical-grade magnesium alloy, pure zinc, or medical-grade zinc alloy with a biodegradability of not less than 99.9 wt%. Preferably, the high-purity magnesium is 99.99 wt% ultra-high purity magnesium. The technical solution of this embodiment has the following advantages: 1. A perfect combination of biomimetic structure and mechanical properties: Utilizing the optimal hexagonal honeycomb structure found in nature, this structure possesses the highest specific stiffness and specific strength in material mechanics. This invention miniaturizes it to the micrometer scale and applies it to a metal mesh. This allows the metal mesh to maintain a high porosity (typically >50%) to facilitate material exchange and cell migration, while possessing mechanical support capabilities far exceeding those of similar biodegradable polymer membranes. It can effectively resist soft tissue pressure within the oral cavity, providing a durable and stable space for bone regeneration.

[0037] 2. Optimized degradation behavior and biological function: (1) The use of biodegradable metals such as high-purity magnesium (99.9%) and ultra-high-purity magnesium (99.99%) or medical magnesium alloy or pure zinc or medical zinc alloy significantly reduces the accelerating effect of impurity elements on electrochemical corrosion, making the degradation rate more uniform and controllable, and the degradation product magnesium ions are known to be potent osteogenic promoting factors.

[0038] (2) The honeycomb structure distributes the degradation area evenly, avoiding the rapid fracture caused by stress concentration in the "narrow bridge" area between traditional round holes, making the degradation process more gradual and controllable, and the degradation cycle more easily matched with the 4-6 month bone regeneration cycle.

[0039] 3. Excellent biocompatibility and selective barrier function: The selected high-purity magnesium, ultra-high-purity magnesium, or medical-grade magnesium alloy, or pure zinc or medical-grade zinc alloy have excellent biocompatibility. The pore size (0.5-1.2mm) of the honeycomb cells is carefully designed to allow the free passage of body fluids, nutrients, and osteoblast-related cells, while effectively blocking the invasion of larger fibroblasts, achieving an ideal "selective barrier" function.

[0040] 4. Convenient Clinical Operation and Personalized Fit: The metal mesh possesses a certain degree of flexibility, allowing surgeons to precisely bend and shape it according to the bone defect during surgery. Pre-set fixing holes and matching screws at the edges ensure secure implant fixation, simplifying the operation. Combined with 3D printing wax model technology, rapid customization to the individual patient's bone defect morphology is possible, improving surgical fit and success rate.

[0041] 5. High-precision, repeatable advanced manufacturing process: The combined process of "3D printing wax pattern + precision embedding casting" is completed under argon protection, effectively preventing the oxidation of biodegradable metals. This process enables high-fidelity and high-consistency forming of complex biomimetic honeycomb structures, ensuring dense internal structure, few defects, and good batch stability of the castings, providing process assurance for the reliability of product mechanical properties and the predictability of degradation behavior.

[0042] The biodegradable porous metal mesh of the present invention for oral and maxillofacial bone repair can be used to prepare a medical device for guiding bone regeneration in maxillofacial surgery for bone defect repair. It can be used as a biodegradable metal barrier membrane to guide bone regeneration and repair bone defects in oral implant, maxillofacial surgery, alveolar ridge augmentation and other surgeries. Its biomimetic porous structure provides mechanical support, controls tissue growth and is eventually safely degraded in vivo.

[0043] Example 2 A method for preparing a biodegradable porous metal mesh for oral and maxillofacial bone repair, comprising the following steps: S1, 3D Model Design and Wax Model Preparation A three-dimensional digital model of the metal mesh is constructed, and then 3D printing technology is used to print a wax model that matches the shape of the final product using medical casting wax as the material.

[0044] S2, Embedding and Dewaxing The wax pattern is placed in the casting ring and embedded with casting powder to form a mold. Then, it is baked and dewaxed. The baking temperature is 80-120℃ and held for 2-4 hours. Then, the temperature is raised to 380-450℃ and held for 1-2 hours to complete the dewaxing, and a ceramic mold with a honeycomb cavity is obtained.

[0045] S3, Melting and Casting Under an argon protective atmosphere, the biodegradable metal raw material is melted. After the metal is completely melted, it is poured into a preheated mold under the same argon protective atmosphere. Specifically, in S3, the melting process is carried out at a melting temperature of 550-700℃ for 30-60 minutes. The preheating temperature of the mold in S3 is 200-300℃, and the preheating holding time is 1-2 hours.

[0046] S4, Cooling and Demolding After pouring, allow it to cool naturally to room temperature, remove the embedding material, and take out the metal mesh casting.

[0047] S5, Post-processing The castings undergo surface cleaning, machining, polishing, and washing to obtain the final biodegradable porous metal mesh. Surface cleaning aims to remove oxide scale and embedded residue from the casting surface; machining aims to correct product dimensions and ensure screw hole accuracy and assembly compatibility; polishing aims to obtain a smooth, burr-free surface and avoid irritating oral tissues; washing aims to thoroughly remove machining residues and ensure biosafety.

[0048] The combined process of "3D printing wax pattern + precision embedding casting" used in this embodiment is completed under argon protection, effectively preventing metal oxidation. This process can achieve high-fidelity and high-consistency forming of complex biomimetic honeycomb structures, ensuring that the internal structure of the casting is dense, with few defects and good batch stability, providing process assurance for the reliability of product mechanical properties and the predictability of degradation behavior.

[0049] Example 3 A method for preparing a biodegradable porous metal mesh for oral and maxillofacial bone repair, comprising the following steps: S1, 3D Model Design and Wax Model Preparation A three-dimensional digital model of the magnesium mesh was constructed, and then 3D printing technology was used to print a wax model with the same shape as the final product using medical casting wax as the material.

[0050] S2, Embedding and Dewaxing The wax pattern is placed in the casting ring and embedded with casting powder to form a mold. Then, it is baked and dewaxed. The baking temperature is 85-100℃ and held for 2-4 hours. Then, the temperature is raised to 380-450℃ and held for 1-2 hours to complete the dewaxing, and a ceramic mold with a honeycomb cavity is obtained.

[0051] S3, Melting and Casting Magnesium raw materials are melted under an argon protective atmosphere. After the metal is completely melted, it is poured into a preheated mold under the same argon protective atmosphere. Specifically, in S3, the melting process is carried out at a melting temperature of 550-700℃ for 30-60 minutes. The preheating temperature of the mold in S3 is 200-300℃, and the preheating holding time is 1-2 hours.

[0052] S4, Cooling and Demolding After pouring, allow it to cool naturally to room temperature, remove the embedded material, and take out the magnesium mesh casting.

[0053] S5, Post-processing The castings undergo surface cleaning, machining, polishing, and washing to obtain the final biodegradable porous metal mesh. Surface cleaning aims to remove oxide scale and embedded residue from the casting surface; machining aims to correct product dimensions and ensure screw hole accuracy and assembly compatibility; polishing aims to obtain a smooth, burr-free surface and avoid irritating oral tissues; washing aims to thoroughly remove machining residues and ensure biosafety.

[0054] The combined process of "3D printing wax pattern + precision embedding casting" used in this embodiment, completed under argon protection, effectively prevents magnesium oxidation. This process enables high-fidelity and high-consistency forming of complex biomimetic honeycomb structures, ensuring dense internal structure, few defects, and good batch stability of the castings. This provides process assurance for the reliability of product mechanical properties and the predictability of degradation behavior.

[0055] Biodegradable porous magnesium mesh was prepared using the method of this embodiment. Multiple samples were prepared, and six groups of samples were selected as examples. The preparation process of each sample is shown in Table 1.

[0056] Table 1 Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sample 6 raw material 99.9 wt% ultra-high purity magnesium 99.99wt% ultra-high purity magnesium Medical magnesium alloy Medical magnesium alloy 99.9 wt% ultra-high purity magnesium Medical magnesium alloy Embedding Baking temperature is 85℃, keep warm for 2 hours. Baking temperature is 100℃, keep warm for 4 hours. Baking temperature is 90℃, keep warm for 3 hours. Baking temperature is 95℃, keep warm for 2.5 hours. Baking temperature is 88℃, keep warm for 3.5 hours. Baking temperature is 96℃, keep warm for 4 hours. Dewaxing Heat to 380℃ and keep warm for 1 hour. Heat to 450℃ and hold for 2 hours. Heat to 400℃ and hold for 1.5 hours. Heat to 390°C and maintain the temperature for 1.2 hours. Heat to 420℃ and hold for 1.5 hours. Heat to 430℃ and hold for 2 hours. Smelting The melting temperature is 550℃, and the holding time is 30 minutes. Melting temperature 700℃, hold for 60 minutes Melting temperature 600℃, hold for 40 minutes The melting temperature is 630℃ and the holding time is 45 minutes. The melting temperature is 650℃ and the holding time is 50 minutes. The melting temperature is 580℃ and the holding time is 35 minutes. mold preheating temperature The mold preheating temperature is 200℃, and the preheating holding time is 1 hour. The mold preheating temperature is 300℃, and the preheating holding time is 2 hours. The mold preheating temperature is 250℃, and the preheating holding time is 1.5 hours. The mold preheating temperature is 280℃, and the preheating holding time is 1.5 hours. The mold preheating temperature is 220℃, and the preheating holding time is 2 hours. The mold preheating temperature is 260℃, and the preheating holding time is 1.5 hours. The performance of samples 1 to 6 was tested and verified. The results showed that the biodegradable porous magnesium meshes of samples 1 to 6 all met the requirements of reasonable structural design, excellent mechanical properties and controllable degradation behavior, and met the degradation requirements, thus achieving the ideal "selective barrier" function.

[0057] Example 4 A method for preparing a biodegradable porous metal mesh for oral and maxillofacial bone repair, comprising the following steps: S1, 3D Model Design and Wax Model Preparation A three-dimensional digital model of the zinc mesh is constructed, and then 3D printing technology is used to print a wax model that matches the shape of the final product using medical casting wax as the material.

[0058] S2, Embedding and Dewaxing The wax pattern is placed in the casting ring and embedded with casting powder to form a mold. Then, it is baked and dewaxed. The baking temperature is 90℃ and held for 2-4 hours. Then, the temperature is raised to 400℃ and held for 2 hours to complete the dewaxing, and a ceramic mold with a honeycomb cavity is obtained.

[0059] S3, Melting and Casting Under an argon protective atmosphere, the zinc raw material is melted. After the metal is completely melted, it is poured into a preheated mold under an argon protective atmosphere. Specifically, in S3, the melting is carried out at a melting temperature of 60°C for 40 minutes. The preheating temperature of the mold in S3 is 250°C, and the preheating holding time is 1.5 hours.

[0060] S4, Cooling and Demolding After pouring, allow it to cool naturally to room temperature, remove the embedding material, and take out the zinc mesh casting.

[0061] S5, Post-processing The castings undergo surface cleaning, machining, polishing, and washing to obtain the final biodegradable porous metal mesh. Surface cleaning aims to remove oxide scale and embedded residue from the casting surface; machining aims to correct product dimensions and ensure screw hole accuracy and assembly compatibility; polishing aims to obtain a smooth, burr-free surface and avoid irritating oral tissues; washing aims to thoroughly remove machining residues and ensure biosafety.

[0062] The combined process of "3D printing wax pattern + precision embedding casting" used in this embodiment is completed under argon protection, effectively preventing zinc oxidation. This process can achieve high-fidelity and high-consistency forming of complex biomimetic honeycomb structures, ensuring that the internal structure of the casting is dense, with few defects and good batch stability, providing process assurance for the reliability of product mechanical properties and the predictability of degradation behavior.

[0063] Example 5 A method for preparing a biodegradable porous metal mesh for oral and maxillofacial bone repair involves preparing a biodegradable porous zinc mesh as described in Examples 1 or 4. Multiple samples were prepared, and six groups of samples were selected as examples. The preparation process for each sample is shown in Table 2.

[0064] Table 2 Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sample 6 raw material 99.9 wt% ultra-high purity zinc 99.99wt% ultra-high purity zinc Medical zinc alloy Medical zinc alloy 99.9 wt% ultra-high purity zinc Medical zinc alloy Embedding Baking temperature is 88℃, keep warm for 2 hours. Baking temperature is 90℃, keep warm for 4 hours. Baking temperature is 92℃, keep warm for 3 hours. Baking temperature is 95℃, keep warm for 2.5 hours. Baking temperature is 85℃, keep warm for 3.5 hours. Baking temperature is 96℃, keep warm for 4 hours. Dewaxing Heat to 390℃ and hold for 1 hour. Heat to 400℃ and hold for 2 hours. Heat to 400℃ and hold for 1.5 hours. Heat to 390°C and maintain the temperature for 1.2 hours. Heat to 380℃ and hold for 1.5 hours. Heat to 430℃ and hold for 2 hours. Smelting The melting temperature is 560℃, and the holding time is 30 minutes. Melting temperature 700℃, hold for 60 minutes The melting temperature is 650℃ and the holding time is 40 minutes. The melting temperature is 620℃ and the holding time is 45 minutes. The melting temperature is 650℃ and the holding time is 50 minutes. The melting temperature is 580℃ and held for 35 minutes. mold preheating temperature The mold preheating temperature is 220℃, and the preheating holding time is 1 hour. The mold preheating temperature is 300℃, and the preheating holding time is 2 hours. The mold preheating temperature is 280℃, and the preheating holding time is 1.5 hours. The mold preheating temperature is 275℃, and the preheating holding time is 1.5 hours. The mold preheating temperature is 220℃, and the preheating holding time is 2 hours. The mold preheating temperature is 230℃, and the preheating holding time is 1.5 hours. The performance of samples 1 to 6 was experimentally verified. The results showed that the biodegradable porous zinc meshes of samples 1 to 6 all met the requirements of reasonable structural design, excellent mechanical properties, and controllable degradation behavior, and thus met the degradation requirements. These samples were then used to prepare guided bone regeneration medical devices for maxillofacial surgery bone defect repair. The experimental results showed that they can serve as biodegradable metal barrier membranes for guiding bone regeneration, and can be used in dental implant surgery, maxillofacial surgery, alveolar ridge augmentation, and other procedures to repair bone defects. Furthermore, their biomimetic porous structure provides mechanical support, controls tissue growth, and ultimately degrades safely in vivo.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A biodegradable porous metal mesh for oral and maxillofacial bone repair, characterized in that: It has a membrane body made of a biodegradable metal, the membrane body having a honeycomb-like perforated structure; The cross-section of the honeycomb-shaped through-hole structure is composed of multiple regular hexagons. Any one of the regular hexagons is used as the central regular hexagon, and any adjacent regular hexagons share a side with the central regular hexagon. They are arranged radially in sequence to form the cross-section of the overall honeycomb-shaped through-hole structure. The diameter of the inscribed circle of any regular hexagon is 0.5-1.2 mm, and the wall thickness of the hole between adjacent regular hexagons is 100-500 μm.

2. The biodegradable porous metal mesh for oral and maxillofacial bone repair according to claim 1, characterized in that: The thickness of the membrane body is 0.3-2 mm.

3. The biodegradable porous metal mesh for oral and maxillofacial bone repair according to claim 1 or 2, characterized in that: The biodegradable metal is ultra-high purity magnesium or medical-grade magnesium alloy or pure zinc or medical-grade zinc alloy with a content of not less than 99.9 wt%.

4. The biodegradable porous metal mesh for oral and maxillofacial bone repair according to claim 1 or 2, characterized in that: The edge of the membrane body is provided with screw holes for fixing.

5. The biodegradable porous metal mesh for oral and maxillofacial bone repair according to claim 4, characterized in that: The diameter of the screw hole is 0.8-2.5 mm.

6. A method for preparing a biodegradable porous metal mesh for oral and maxillofacial bone repair as described in any one of claims 1 to 5, characterized in that, Includes the following steps: S1, 3D model design and wax model preparation, specifically: constructing a 3D digital model of a metal mesh, and then using 3D printing technology, using medical casting wax as the material, to print a wax model that is consistent with the shape of the final product; S2, embedding and dewaxing, specifically: placing the wax pattern inside the casting ring, embedding it with casting powder to form a mold; then baking and dewaxing are performed to obtain a ceramic mold with a honeycomb cavity; S3, Melting and Casting, specifically: under an argon protective atmosphere, the biodegradable metal raw material is melted, and after the metal is completely melted, it is poured into a preheated mold under a protective atmosphere. S4, Cooling and Demolding: After pouring, allow the material to cool naturally to room temperature, remove the embedded material, and take out the metal mesh casting. S5, Post-processing: The casting is surface cleaned, machined, polished and cleaned to obtain the final biodegradable porous metal mesh.

7. The method for preparing the biodegradable porous metal mesh for oral and maxillofacial bone repair as described in any one of claims 1 to 5, as described in claim 6, is characterized in that: In S2, the baking and dewaxing process is as follows: the baking temperature is 80-120℃, and the temperature is maintained for 2-4 hours; then the temperature is raised to 380-450℃, and the temperature is maintained for 1-2 hours to complete the dewaxing.

8. The method for preparing a biodegradable porous metal mesh for oral and maxillofacial bone repair as described in any one of claims 1 to 5, as described in claim 6, is characterized in that: Specifically, in S3, the melting process involves holding the material at a melting temperature of 550-700℃ for 30-60 minutes.

9. The method for preparing a biodegradable porous metal mesh for oral and maxillofacial bone repair as described in any one of claims 1 to 5, as described in claim 6, is characterized in that: The preheating temperature of the mold in S3 is 200-300℃, and the preheating holding time is 1-2 hours.

10. Use of the biodegradable porous metal mesh for oral and maxillofacial bone repair according to any one of claims 1 to 5 in the preparation of a guided bone regeneration medical device for repairing bone defects in maxillofacial surgery.

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