Preparation method of interpenetrating phase ceramic dental material

Abstract

The invention discloses a preparation method of an interpenetrating phase ceramic dental material, and belongs to the technical field of biomedical materials. Bionic design is carried out based on a porous foam structure and a cavity tissue of bird bones, two bionic bird bone structures combining annular tongue bone structure characteristics and the cavity tissue are established, mortise and tenon matching design is carried out according to a bird skull collaborative vibration reduction mechanism, and the bionic bird bone mortise and tenon structure with collaborative bearing and buffering characteristics is constructed. Compared with a traditional structure, the structure has more excellent mechanical bearing performance and deformation stability. According to the zirconia-hydrogel interpenetrating phase material prepared by a photo-crosslinking method, due to the composite design of a soft-phase material and a hard-phase material, the energy absorption characteristic of the material is remarkably improved, and meanwhile, the fracture toughness of a dental material is effectively improved. On the basis, a functional coating is constructed on the surface of the material by adopting a sol-gel dip-coating process, so that the problem that the dental material is insufficient in corrosion resistance and wear resistance in an oral environment is further solved.

Description

Technical Field

[0001] This invention belongs to the field of biomedical materials technology, specifically, it relates to a method for preparing an interpenetrating phase ceramic dental material. Background Technology

[0002] Zirconia ceramics have become a key material in modern dental restorations due to their excellent biocompatibility, high strength, and high wear resistance. However, the Young's modulus of conventional dense zirconia is much higher than that of natural dentin. This mismatch in mechanical properties can easily lead to stress shielding effects and may cause excessive wear of opposing teeth. More importantly, its inherent brittleness and crack sensitivity limit its long-term reliability under dynamic occlusal loads.

[0003] Meanwhile, with the development of additive manufacturing technology in recent years, researchers have gradually applied classic pyramid lattice structures, traditional body-centered cubic (BCC) structures, and traditional face-centered cubic (FCC) structures to dental materials. However, these structures have insufficient load-bearing capacity and are prone to stress concentration leading to failure, making them unsuitable for long-term and effective service. Therefore, a new structural design is needed to overcome these shortcomings, and biomimetic design has been proven to be more mechanically feasible than traditional structures in fields such as medical implants, aerospace, and automotive protection.

[0004] Dental restorations endure complex cyclic chewing forces and impact loads in the oral cavity over long periods, and the fracture toughness of the material directly determines its clinical lifespan and reliability. Traditional zirconia ceramics primarily rely on phase transformation toughening, which carries the risk of aging in the later stages of service and has limited ability to inhibit crack propagation. In contrast, the unique three-dimensional interpenetrating network structure of interpenetrating phase heterostructure materials developed in recent years enables multiple toughening mechanisms: when the main crack propagates within the hard phase framework, the flexible soft phase network absorbs energy through deformation and effectively transfers and disperses stress through the two-phase interface.

[0005] Furthermore, in the complex chemical and mechanical environment of the oral cavity, the long-term service performance of materials faces severe challenges, and the corrosion resistance and wear resistance of their surfaces directly determine the clinical lifespan and functional reliability of the restorations. While zirconia stabilized with yttrium oxide (3Y-TZP) exhibits excellent mechanical properties at room temperature, it suffers from "low-temperature aging" in the warm and humid environment of the oral cavity. Although increasing the yttrium oxide content in zirconia or using alumina-based multiphase technology to create composite materials can alleviate the "low-temperature aging" problem, this often comes at the cost of sacrificing its high toughness. Surface-modified coating techniques, however, promise to solve these problems without affecting the material's mechanical properties and weight. Summary of the Invention

[0006] To address the aforementioned problems in the existing technology, the present invention aims to provide a method for preparing interpenetrating phase ceramic dental materials.

[0007] To solve the above problems, the technical solution adopted by the present invention is as follows: A method for preparing an interpenetrating phase ceramic dental material includes the following steps: Step 1: Based on 3D modeling software, complete the establishment of the biomimetic bird bone mortise and tenon structure. The biomimetic bird bone mortise and tenon structure includes two biomimetic bird bone structures. The two different biomimetic bird bone structures are connected to each other by mortise and tenon to form the model of the biomimetic bird bone mortise and tenon structure. Step 2: Import the biomimetic bird bone tenon structure designed in Step 1 into the model slicing software for model slicing. Based on photopolymerization technology, use zirconia slurry to print the biomimetic bird bone tenon structure. Then, degrease and sinter it to obtain a biomimetic bird bone tenon structure with zirconia ceramic as the matrix. Step 3: The biomimetic bird bone tenon structure with zirconia ceramic as the matrix is ​​prepared into a zirconia-hydrogel interpenetrating phase structure by in-situ photocrosslinking. Step four involves applying a multifunctional composite coating to the zirconia-hydrogel interpenetrating phase structure obtained in step three using a sol-gel dip-coating method, thereby preparing a multi-layered zirconia-hydrogel biomimetic bird bone structure.

[0008] Furthermore, the biomimetic bird bone structure includes an R-type biomimetic bird bone structure and a Y-type biomimetic bird bone structure.

[0009] Furthermore, the method for establishing the R-shaped bionic bird bone structure is as follows: First, draw an equilateral triangle based on the front reference plane. Then, extrude the equilateral triangle to obtain a triangular prism structure with a length greater than the side length of the equilateral triangle. The faces containing the two equilateral triangles of the triangular prism are defined as the top face and the bottom face, and the face containing the quadrilateral is defined as the side face. Take any two long sides of the triangular prism as reference axis 1 and reference axis 2. Draw a perpendicular line between reference axis 2 and the bottom side on the top face. Based on the perpendicular line and reference axis 2, construct reference plane 0. Draw a circle with a diameter smaller than the side length of an equilateral triangle on the side of the triangular prism, and the circle is a certain distance away from the top or bottom surface of the triangular prism. Select the circle and perform a rotation cut based on the reference axis 1 to obtain a ring cut feature connecting two sides inside the triangular prism. Then, mirror the ring cut feature based on the reference plane 0 to obtain a cut feature connecting three sides. Finally, array the cut feature multiple times along the long side of the triangular prism and perform cuts to obtain a triangular prism with multiple three-sided interconnected openings. The triangular prism after the hole is made is bent twice. The first bending operation is a twisting operation with a twisting angle of 360 degrees, and the entire triangular prism is twisted once. The second bending operation is a bending operation, and the twisted triangular prism is connected end to end to form a ring. Place the ring structure horizontally, and use the right-view reference plane as the reference plane offset by a certain distance towards the ring structure to form reference plane 1, and the top-view reference plane as the reference plane offset by a certain distance towards the ring structure to form reference plane 2. Then, mirror the ring structure once based on reference plane 1. Finally, mirror the mirrored structure once again based on reference plane 2 to obtain the R-shaped bionic bird bone structure unit. Define reference plane 1 as parallel to the plane formed by the Y-axis and Z-axis, and reference plane 2 as parallel to the plane formed by the X-axis and Y-axis. Construct a coordinate system based on the two reference planes. First, array the R-type bionic bird bone structure unit three times along the Y-axis, and then array the structure three times again along the Z-axis. A total of nine R-type bionic bird bone structure units are included, and finally the R-type bionic bird bone structure is obtained.

[0010] Furthermore, the method for establishing the Y-shaped bionic bird bone structure is as follows: Create a square sketch of length f and height g based on the front reference plane. Take the midpoint of the top and the bottom left endpoint of the square sketch and create a spline curve between the two points. Name the two endpoints A and C, and name the midpoint of the spline curve B. The angles of the spline curve vertices A and C along the tangent radial direction are both -27.5°, and the radius of curvature at the vertices is f / 2. The angle of point B along the tangent radial direction is -55°, and the radius of curvature is set to f+g. The corresponding spline curve is obtained. Then, the spline curve is mirrored with the straight line of the square sketch passing through the center point and point A as the reference to obtain the projection reference. Then draw the projection path. The projection path is drawn based on the left view reference plane. The projection path uses the top and bottom vertices of the square sketch as endpoints to construct an arc with a radius of r1. The projection reference is projected onto the projection path to obtain a projection curve that curves on the left view reference plane. Then, the projection curve is scanned with a circular outline of diameter D1 to obtain the solid structure. The X-axis is defined by the length f in the square sketch, the Z-axis by the height g, and the Y-axis by the direction perpendicular to both the X-axis and the Z-axis. The solid structure is arrayed five times along the Z-axis with an array distance of g / 2. The arrayed solid structure is then arrayed five times along the X-axis with an array distance of f. Finally, the arrayed solid structure is mirrored along the front reference plane to obtain the Y-shaped bionic bird bone structure unit. The Y-shaped bionic bird bone structure units are arranged three times along the Y-axis, resulting in a total of three Y-shaped bionic bird bone structure units, thus obtaining the Y-shaped bionic bird bone structure.

[0011] Furthermore, the dimensions and aspect ratios of the two biomimetic bird bone structures in step one are the same.

[0012] Furthermore, the zirconium oxide slurry formulation in step two is as follows: 85 wt% of 3Y-TZP zirconia powder was mixed with 4.5 wt% HDDA, 3.0 wt% PEG400DA, 0.5 wt% photoinitiator and 2.0 wt% dispersant, and the mixture was vacuum stirred at 2000 rpm for 40 minutes using a planetary centrifuge to obtain a homogeneous and stable slurry with a solid content of 52 vol%.

[0013] Furthermore, the photopolymerization printing parameters in step two are as follows: The printing was performed using parameters of 6 seconds for single-layer exposure, 35 seconds for bottom layer exposure, 50μm for single-layer thickness, and 15mW / cm² light intensity. After ultrasonic cleaning and drying, the printed green body undergoes programmed degreasing and sintering to finally obtain a biomimetic bird bone tenon and mortise structure with zirconia ceramic as the matrix.

[0014] Furthermore, the specific steps of degreasing and sintering in step two are as follows: The degreasing process is carried out in an air atmosphere, and the specific steps are as follows: The temperature was increased to 200℃ at 1℃ / min and held for 30 minutes, then increased to 500℃ at 0.5℃ / min and held for 120 minutes, and finally increased to 600℃ at 1℃ / min and held for 60 minutes, and then cooled in the furnace. The degreased ceramic blanks are placed in a high-temperature sintering furnace and sintered in air atmosphere. The specific steps are as follows: The temperature was increased to 1000℃ at 5℃ / min without holding, and then increased to the final sintering temperature of 1500℃ at 2℃ / min. The temperature was held at this temperature for 120 minutes to achieve complete densification. Finally, the temperature was controlled to be cooled to below 1000℃ at a rate of 3℃ / min, and then cooled to room temperature in the furnace. The result was a biomimetic bird bone tenon structure with zirconia ceramic as the matrix.

[0015] Furthermore, the specific preparation steps for the in-situ photocrosslinking method to prepare the zirconia-hydrogel interpenetrating phase structure in step three are as follows: Using phosphate buffer as the sole solvent, solid powdered methacrylamide gelatin and solid powdered photoinitiator Irgacure 2959 were dissolved to achieve a concentration of 15% w / v and 0.5% w / v respectively. The solutions were stirred in a 60°C water bath until both solutes were completely dissolved, and then placed at 4°C to remove bubbles before use as precursor solutions. The biomimetic bird bone tenon structure with zirconia ceramic as the matrix obtained in step two was treated with oxygen plasma, then completely immersed in the precursor solution, and impregnated for 30 minutes under a vacuum of -0.1 MPa. After impregnation, the sample was transferred to 365nm ultraviolet light and irradiated for 75 seconds in a nitrogen atmosphere with a light intensity of 8mW / cm², so that the methacrylamide gelatin was photopolymerized in situ inside the biomimetic bird bone tenon and mortise structure to form a stable zirconium oxide-hydrogel interpenetrating phase structure.

[0016] Furthermore, the specific method for preparing the multi-layered zirconia-hydrogel biomimetic bird bone structure using sol-gel dip-coating in step four is as follows: Sol preparation: Tetraethyl orthosilicate, ethanol, water and catalyst are mixed in a certain proportion and stirred and hydrolyzed at a certain temperature to form a stable SiO2 sol; Dip coating: The zirconium oxide-hydrogel interpenetrating phase structure is completely immersed in the prepared sol and kept for a period of time to ensure that the inner and outer surfaces are fully wetted; Soluble extraction: The zirconia-hydrogel interpenetrating phase structure is extracted from the sol at a constant and slow speed to form a uniform liquid film on its surface; Heat treatment: The zirconium oxide-hydrogel interpenetrating phase structure after pulling is first dried at 50-100℃, and then heat-treated at 400-600℃ to evaporate the solvent and decompose the organic matter, ultimately forming an amorphous, dense SiO2-based glass-ceramic coating on the surface of the zirconium oxide-hydrogel interpenetrating phase structure. Compared with the prior art, the advantages of this invention are: Inspired by natural biological composite materials such as bird skeletons, two types of biomimetic bird skull structures were designed that combine the characteristics of the hollow tissue of bird skulls and the cricoid hyoid bone. The two skull structures were then joined together in a mortise and tenon joint to form a biomimetic bird mortise and tenon structure. This structure mimics the synergistic mechanism of vibration damping in bird skeletons and achieves lightweight, high toughness and efficient energy dissipation compared to traditional support forms.

[0017] By introducing a hydrogel phase to form a three-dimensional interpenetrating structure, multiple toughening mechanisms can be achieved: when the main crack propagates within the zirconia framework, the flexible hydrogel network absorbs energy through its significant viscoelastic deformation and effectively transfers and disperses stress through the two-phase interface, inducing crack deflection, bridging, and even pinning, thereby significantly blunting the crack tip and inhibiting its unstable propagation. This comprehensive improvement in toughness can significantly reduce the risk of porcelain chipping or fracture of restorations due to fatigue loads or accidental impacts during clinical use, improving the long-term safety and durability of dental crowns, bridges, and other restorative structures.

[0018] A sol-gel dip-coating technique was employed to immerse the interpenetrating phase composite material in a composite sol using tetraethyl orthosilicate and tetrabutyl titanate as precursors. Following uniform pulling and programmed heat treatment (up to 600℃), a dense SiO2-TiO2 hybrid glass coating with a thickness of approximately 200 nanometers was formed on the surface. This coating not only effectively seals surface micro-defects, but its inherent chemical inertness also endows the material with excellent resistance to acid corrosion. Attached Figure Description

[0019] Figure 1 Schematic diagrams of two biomimetic bird bone structures designed based on different microscopic features of the bird skull and hyoid bone; Figure 2 This is a schematic diagram of the R-shaped biomimetic bird bone structure designed for this invention; Figure 3 This is a schematic diagram of the Y-shaped biomimetic bird bone structure designed for this invention; Figure 4 This is a schematic diagram of the biomimetic bird bone mortise and tenon structure designed for this invention; Figure 5 This is a schematic diagram of the preparation of a zirconia-hydrogel interpenetrating phase structure based on in-situ photocrosslinking; Figure 6 A schematic diagram of the preparation of a multi-level zirconia-hydrogel biomimetic bird bone structure using sol-gel dip-coating technology; Figure 7 A diagram illustrating the effect of a multi-level zirconia-hydrogel biomimetic bird bone structure; In the figure: 11, R-type biomimetic bird bone structure; 110, R-type biomimetic bird bone structure unit; 12, Y-type biomimetic bird bone structure; 120, Y-type biomimetic bird bone structure unit; 2, biomimetic bird bone tenon and mortise structure; 3, zirconia-hydrogel interpenetrating phase structure; 4, multi-level zirconia-hydrogel biomimetic bird bone structure. Detailed Implementation

[0020] The present invention will be further described below with reference to specific embodiments.

[0021] This design is based on biomimetic design of the microstructure of the woodpecker's skeleton in nature. For example... Figure 1 As shown, the woodpecker's skull, especially the forehead region, exhibits a highly developed porous, foam-like structure. This specialized, super-porous structure acts like a highly efficient "natural energy absorber," located between the base of the beak and the brain. Upon impact, this structure absorbs and disperses energy through the collapse and plastic deformation of its numerous internal micropores, effectively protecting the brain.

[0022] Furthermore, the hyoid bone structure of woodpeckers is particularly well-developed. It doesn't simply encircle the skull; instead, it originates from the back of the lower jaw, branches upwards and backwards in two directions, passing above the nostrils, and finally converging at the forehead to form a ring-shaped support system covering the entire top of the skull. The entire hyoid bone acts like a built-in "safety helmet skeleton," completely enveloping the brain. This unique pathway allows it to apply effective damping restraint to the skull from multiple directions—front, back, left, and right. Regardless of whether the impact primarily comes from the front or other directions, the hyoid bone system can be activated and participate in overall shock absorption, demonstrating outstanding multi-directional protection and synergistic buffering capabilities.

[0023] like Figure 1 As shown, the skull cavity features and hyoid bone ring characteristics of the woodpecker skeletal system were extracted and integrated into the bionic skeleton. Based on this, two bionic bird bone structures were designed, including the R-type bionic bird bone structure 11, abbreviated as BBSTR (Bionic-bird bone structure type R), and the Y-type bionic bird bone structure 12, abbreviated as BBSTY (Bionic-bird bone structure type Y).

[0024] like Figure 2 As shown, the function commands used in this embodiment are all selected from the Solidworks software. When using other modeling software, the model can also be constructed using commands with the same functions. The design steps of the R-type bionic bird bone structure 11 are as follows: First, commands such as stretching, cutting, mirroring, and arraying are performed to create a regular triangular prism with a circular hole.

[0025] The method for constructing a regular triangular prism with a circular hole is as follows: Using the previous reference plane as a reference, draw an equilateral triangle with side length *a* at the default origin. Then, perform a solid extrusion operation on this triangle, with an extrusion length of *b*, which is much greater than the side length *a* of the equilateral triangle. Define the faces containing the two equilateral triangles of the prism as the top and bottom faces, respectively, and the face containing the quadrilateral as the side face. Simultaneously, construct reference axis 1 and reference axis 2 using the two sides of the regular triangular prism. Draw a perpendicular line from reference axis 2 to the bottom face on the top face. Based on this perpendicular line and reference axis 2, construct reference plane 0.

[0026] The cut command is then performed on the top reference plane. A circle with a diameter of d is drawn on the side of the triangular prism, and the diameter of the circle is smaller than the side length of the equilateral triangle. The circle is a certain distance away from the top or bottom surface of the triangular prism. The circle is selected and a rotation cut command is performed with reference axis 1 as the reference to complete the initial modeling of the hole. Then, the annular cut feature is mirrored with reference plane 0 to obtain a cut feature that connects the three sides. This command ensures that there are holes on all three sides of the triangular prism. Then, the feature array is performed with the front reference plane as the reference, and the three holes are arrayed with an instance number of seven to complete the establishment of the reference model.

[0027] After the baseline model is established, two bending operation commands are executed. The first bending operation uses a twisting motion with a twist angle of 360 degrees. The second bending operation uses a folding motion with an angle of 359.5 degrees and a folding radius of 55.78 mm. The baseline triple axes are defined as 0, 0, and 90 degrees. This completes the initial construction of the single unit (i.e., the ring structure). Next, the initial unit is rounded. Rounded corners, compared to sharp angles, can alleviate stress concentration under load. Simultaneously, using the right-view and top-view reference planes as references, reference planes 1 and 2 are constructed at distances d and e from the ring structure, parallel to the right-view and top-view reference planes, respectively. In this embodiment, reference plane 1 is defined to be parallel to the plane formed by the Y-axis and Z-axis, and reference plane 2 is defined to be parallel to the plane formed by the X-axis and Y-axis. A coordinate system is constructed using these two reference planes.

[0028] Subsequently, the ring structure was mirrored using reference plane 1 and reference plane 2 respectively, resulting in an R-shaped bionic bird bone structure unit 110 with dimensions X1×Y1×Z1. Finally, the R-shaped bionic bird bone structure unit 110 was first arrayed three times along the Y-axis at a distance of Y1, and then the arrayed structure was arrayed three times along the Z-axis at a distance of Z1. The arrayed structure contained a total of nine R-shaped bionic bird bone structure units 110. These were then combined to form the final solid structure, resulting in the R-shaped bionic bird bone structure 11.

[0029] like Figure 3 As shown, the design steps of the Y-shaped biomimetic bird bone structure 12 are as follows: Draw the first curve as the projection datum: Create a square sketch of length f and height g, using the front reference plane as the reference. Draw a spline curve on the square sketch, passing through points A, B, and C in the diagram. Point A is the midpoint of the top of the square sketch, point C is the left endpoint of the bottom of the square sketch, and point B is the middle point. Set the angles of the top and bottom vertices A and C along the tangent radial direction to -27.5°, and the radius of curvature at vertices A and C to f / 2. Set the angle of the middle vertex B along the tangent radial direction to -55°, and the radius of curvature to f+g. Then, mirror the spline curve using the straight line passing through the center point and point A of the square sketch as the reference to obtain the projection datum.

[0030] Then draw the second curve as the projection path: the projection path is drawn on the left view reference plane, and an arc is constructed through the top and bottom vertices of the square sketch with a radius of r1.

[0031] Subsequently, the two curves mentioned above are selected respectively, and the projection curve command is executed. The second curve is selected as the projection path, and the first curve is selected as the projection reference sketch outline. After projection, the projection curve is obtained, which is the projection reference that is bent on the projection path. In this embodiment, the direction of length f in the square sketch is determined as the X-axis, the direction of height g is determined as the Z-axis, and the direction perpendicular to the X-axis and Z-axis is the Y-axis.

[0032] Then, execute the scan command on the projection curve. The scan contour is a circular contour by default, and the diameter of the circular contour is D1, thus obtaining the solid structure.

[0033] The solid structure is arrayed five times along the Z-axis with an array distance of g / 2. The arrayed solid structure is then arrayed five times along the X-axis with an array distance of f. Subsequently, the linear solid structure is mirrored using the front-view reference plane, forming a Y-shaped bionic bird bone structure unit 120 with dimensions X2×Y2×Z2. Finally, the Y-shaped bionic bird bone structure unit 120 is arrayed three times along the Y-axis with an array distance of Y2, forming a Y-shaped bionic bird bone structure 12.

[0034] The woodpecker's hyoid bone forms a complete ring, nesting the core area of ​​its skull within it. This is similar to a ring-shaped, closed "hoop" or "frame," creating a nested mortise and tenon system with the skull. This structure greatly enhances the overall stability of the system, preventing instability and dislocation of parts under impact, and ensuring the reliability and controllability of the energy transfer path.

[0035] Drawing inspiration from the woodpecker's mortise and tenon joint system, the structure was further optimized, such as... Figure 4As shown, the R-type bionic bird bone structure 11 and the Y-type bionic bird bone structure 12 are scaled down to X3×Y3×Z3 to ensure consistent dimensions. Then, a mortise and tenon joint is used, interlocking the contact portions of the Y-type and R-type bionic bird bone structures 12 and 11. Specifically, the scanned edge of the Y-type structure 12 is inserted into the hole of the R-type structure 11, forming a bionic bird bone mortise and tenon structure 2 with both R-type and Y-type structures 11. This is abbreviated as BBMS (Bionic-bird bone mortise-and-tenon structure). In this embodiment, the bionic bird bone mortise and tenon structure 2 is composed of three R-type and three Y-type structures 12. Figure 4 The BBMS shown in the diagram represents the final assembled structure. This biomimetic bird bone tenon and mortise structure 2 can achieve a synergistic vibration reduction effect when faced with impacts from different directions.

[0036] After designing the model of the biomimetic bird bone tenon structure 2, the interpenetrating phase ceramic material based on this structure can be manufactured. The specific preparation method is as follows: Step 1: Based on 3D modeling software, complete the creation of the bionic bird bone mortise and tenon structure 2 model. The bionic bird bone mortise and tenon structure 2 includes an R-shaped bionic bird bone structure 11 and a Y-shaped bionic bird bone structure 12. Then, appropriately scale the model to ensure that the dimensions of the R-shaped bionic bird bone structure 11 and the Y-shaped bionic bird bone structure 12 are consistent. Then, use the assembly mating command to complete the mortise and tenon connection, and finally obtain the model of the bionic bird bone mortise and tenon structure 2.

[0037] Step 2: Convert the model of the biomimetic bird bone tenon structure 2 designed in Step 1 into an STL format file and import it into Lychee Slicer software. Based on the Digital Light Processing (DLP) technology, print the biomimetic bird bone tenon structure 2 with zirconia slurry. Then, debinding and sintering are performed to obtain the biomimetic bird bone tenon structure 2 with zirconia ceramic as the matrix.

[0038] Step 3: The biomimetic bird bone tenon structure 2, which uses zirconia ceramic as the matrix in Step 2, is prepared into a zirconia-water gel interpenetrating phase structure 3 (ZGIPS) using an in-situ photocrosslinking method.

[0039] Step 4: Using a sol-gel dip-coating method, a multi-functional composite coating is added to the zirconia-hydrogel interpenetrating phase structure 3 obtained in Step 3 to prepare a multilayered zirconia-water gel biomimetic-bird bone structure 4 (abbreviated as MZGBBS).

[0040] The zirconia slurry formulation in step two is as follows: 85 wt% of 3Y-TZP zirconia powder is mixed with 4.5 wt% HDDA, 3.0 wt% PEG400DA, 0.5 wt% BAPO photoinitiator and 2.0 wt% Hypermer KD-4 dispersant, and then vacuum-stirred at 2000 rpm for 40 minutes using a planetary centrifuge to obtain a uniform and stable slurry with a solid content of 52 vol%.

[0041] The DLP printing parameters in step two are as follows: a single-layer exposure time of 6 seconds, a bottom layer exposure time of 35 seconds, a single-layer thickness of 50 μm, and a light source intensity of 15 mW / cm². The printed green body is ultrasonically cleaned and dried, then subjected to programmed degreasing and sintering to ultimately obtain a biomimetic bird bone tenon and mortise structure 2 with zirconia ceramic as the matrix.

[0042] The degreasing and sintering processes in step two are as follows: The degreasing process is carried out in an air atmosphere, and the specific steps are as follows: the temperature is increased to 200℃ at 1℃ / min and held for 30 minutes, then increased to 500℃ at 0.5℃ / min and held for 120 minutes, and finally increased to 600℃ at 1℃ / min and held for 60 minutes, followed by furnace cooling.

[0043] The degreased ceramic blank was placed in a high-temperature sintering furnace and sintered in an air atmosphere. The specific steps were as follows: the temperature was increased to 1000℃ at 5℃ / min without holding; then the temperature was increased to the final sintering temperature of 1500℃ at 2℃ / min and held at this temperature for 120 minutes to achieve complete densification; finally, the temperature was controlled to be cooled to below 1000℃ at a rate of 3℃ / min, and then cooled to room temperature with the furnace, finally obtaining a biomimetic bird bone tenon and mortise structure 2 with zirconia ceramic as the matrix.

[0044] The molding effect of the in-situ photocrosslinking method for preparing zirconia-hydrogel interpenetrating phase structure 3 in step 3 is as follows: Figure 5 As shown in the figure, the left side is a perspective view of the zirconia-hydrogel interpenetrating phase structure 3, and the right side are the actual morphological images of the R-type biomimetic bird bone structure 11 and the Y-type biomimetic bird bone structure 12 after in-situ photocrosslinking. The specific preparation steps are as follows: First, prepare the precursor solution for later use. The preparation method for the precursor solution is as follows: use phosphate buffered saline (PBS) as the sole solvent to dissolve solid powdered methacrylamide gelatin (GelMA) and solid powdered photoinitiator Irgacure 2959. After the two solutes are prepared into solutions, they should each reach a concentration of 15% w / v and 0.5% w / v (i.e., add 15g GelMA and 0.5g Irgacure 2959 to 100mL of buffer). Stir in a 60℃ water bath until the two solutes are completely dissolved, and then place in a 4℃ environment to remove bubbles for later use.

[0045] The biomimetic bird bone tenon structure 2, with zirconia ceramic as the matrix obtained in step two, was treated with oxygen plasma and then completely immersed in the precursor solution. It was then kept under a vacuum of -0.1 MPa for 30 minutes to achieve sufficient infiltration. Subsequently, the sample was transferred to 365 nm ultraviolet light and irradiated for 75 seconds in a nitrogen atmosphere with a light intensity of 8 mW / cm², causing methacrylamide gelatin to photopolymerize in situ within the biomimetic bird bone tenon structure 2, forming a stable zirconia-hydrogel interpenetrating phase structure 3.

[0046] The molding effect of the multi-layered zirconia-hydrogel biomimetic bird bone structure prepared by sol-gel dip coating is as follows: Figure 6 As shown, the specific steps include sol preparation, dip coating, lifting, and heat treatment.

[0047] Sol preparation: Tetraethyl orthosilicate (TEOS), ethanol, water, and a catalyst (such as HCl) are mixed in a certain proportion and hydrolyzed by stirring at a certain temperature to form a stable SiO2 sol. To improve toughness, a small amount of tetrabutyl titanate can be added to form a SiO2-TiO2 composite sol.

[0048] Dip coating: The zirconium oxide-hydrogel interpenetrating phase structure 3 is completely immersed in the prepared sol and kept for a period of time to ensure that the inner and outer surfaces are fully wetted.

[0049] Lifting: The zirconia-hydrogel interpenetrating phase structure 3 is lifted from the sol at a constant and slow speed to form a uniform liquid film on its surface.

[0050] Heat treatment: First, dry at a low temperature (50~100℃), then heat treat at a higher temperature (400-600℃) to evaporate the solvent and decompose the organic matter, and finally form an amorphous, dense SiO2-based glass ceramic coating on the surface of the zirconium oxide-hydrogel interpenetrating phase structure 3.

[0051] For demonstration of the effects of this invention, please refer to the following. Figure 7As shown: First, traditional zirconia support designs often face the risk of failure and damage, while the biomimetic bird bone tenon structure 2 prepared by this invention can achieve synergistic vibration reduction when faced with impacts from different directions. Moreover, the rounded corners of the structure are less prone to stress concentration than the sharp corners of traditional structures, thus resulting in better load-bearing capacity and more stable deformation mode.

[0052] Secondly, the toughening mechanism of traditional zirconia ceramics mainly relies on phase transformation toughening, which poses an aging risk in the later stages of service and has limited ability to inhibit crack propagation. However, by introducing a hydrogel phase to prepare a zirconia-hydrogel interpenetrating phase structure 3, multiple toughening mechanisms can be achieved: when the main crack propagates in the zirconia framework, the flexible hydrogel network absorbs energy through its huge viscoelastic deformation and effectively transfers and disperses stress through the two-phase interface, inducing crack deflection, bridging, and even pinning, thereby significantly blunting the crack tip and inhibiting its unstable propagation.

[0053] Furthermore, zirconia ceramic materials partially stabilized by yttrium oxide as a stabilizer in existing technologies exhibit "low-temperature aging" in the warm and humid environment of the oral cavity. A multi-layered zirconia-hydrogel biomimetic bird bone structure 4, prepared using a sol-gel dip-coating technique, forms a dense SiO2-TiO2 hybrid glass coating approximately 200 nanometers thick on the surface of the zirconia-hydrogel interpenetrating phase structure 3. This coating not only effectively seals surface micro-defects, but its inherent chemical inertness also endows the material with excellent resistance to acid corrosion.

Claims

1. A method for the production of an interpenetrating phase ceramic dental material, characterized in that, Comprise the following steps: Step one, based on three-dimensional modeling software to complete the establishment of bionic bird bone mortise and tenon structure, bionic bird bone mortise and tenon structure includes two kinds of bionic bird bone structure, two different bionic bird bone structure between each other mortise and tenon connection constitutes the model of bionic bird bone mortise and tenon structure; Step two, the bionic bird bone mortise and tenon structure designed in step one is introduced into the model slicing software to carry out model slicing, based on the light curing technology, the bionic bird bone mortise and tenon structure is printed into zirconia slurry, then debinding and sintering, get zirconia ceramic as the matrix of bionic bird bone mortise and tenon structure; Step three, the in situ light crosslinking method is used to prepare the zirconia-hydrogel interpenetrating phase structure of the bionic bird bone mortise and tenon structure with zirconia ceramic as the matrix; Step four, the sol-gel dip coating method is used to add a multifunctional composite coating to the zirconia-hydrogel interpenetrating phase structure obtained in step three, and a multilevel zirconia-hydrogel bionic bird bone structure is prepared.

2. A method of making an interpenetrating phase ceramic dental material according to claim 1, wherein, The bionic bird bone structure includes R type bionic bird bone structure and Y type bionic bird bone structure.

3. A method of making an interpenetrating phase ceramic dental material according to claim 2, wherein, The establishment method of the R type bionic bird bone structure is as follows: First, an equilateral triangle is drawn based on the front reference plane, then the equilateral triangle is stretched to obtain a triangular prism structure with a length greater than the side length of the equilateral triangle, the two equilateral triangle planes of the triangular prism are defined as the top and bottom planes, the four plane is defined as the side plane, and any two long edges of the triangular prism are taken as the reference axes 1 and 2, a vertical line of the reference axis 2 and the bottom edge is drawn on the top plane, and a reference plane 0 is constructed based on the vertical line and the reference axis 2; A circle with a diameter smaller than the side length of the equilateral triangle is drawn on the side plane of the triangular prism, and the circle is a certain distance from the top or bottom plane of the triangular prism, the circle is selected and rotated based on the reference axis 1 to cut off, a ring-shaped cut feature connecting the two side planes is obtained inside the triangular prism, then the ring-shaped cut feature is mirrored based on the reference plane 0 to obtain a cut feature connecting the three side planes, finally the cut feature is arrayed multiple times along the long edge direction of the triangular prism and cut off, and a triangular prism with multiple three-face interconnected openings is finally obtained; The opened triangular prism is subjected to two bending operations, the first bending operation is a twisting operation with a twisting angle of 360 degrees, and the entire triangular prism is twisted once, the second bending operation is a bending operation, and the twisted triangular prism is connected end to end to form a ring shape; The ring structure is placed horizontally, the right reference plane is offset a certain distance from the ring structure to form a reference plane 1, and the upper reference plane is offset a certain distance from the ring structure to form a reference plane 2, then the ring structure is mirrored once based on the reference plane 1, and finally the mirrored structure is mirrored again based on the reference plane 2, and an R type bionic bird bone structure monomer is finally obtained; The plane composed of the reference plane 1, Y axis and Z axis is defined as parallel, the plane composed of the reference plane 2, X axis and Y axis is defined as parallel, and a coordinate system is constructed based on the two reference planes, the R type bionic bird bone structure monomer is arrayed three times along the Y axis first, then the arrayed structure is arrayed three times along the Z axis again, a total of nine R type bionic bird bone structure monomers are included, and an R type bionic bird bone structure is finally obtained.

4. The method of claim 2, wherein the interpenetrating phase ceramic dental material is prepared by the steps of: The method for establishing the Y-shaped bionic bird bone structure is as follows: A square sketch with a length of f and a height of g is established based on the front reference plane, the midpoint at the top of the square sketch and the endpoint at the left bottom of the square sketch are taken, a spline curve is created between the two points, the two endpoints are named as A and C, the midpoint of the spline curve is named as B, the angles of the spline curve vertices A and C along the tangent radial direction are both-27.5, the curvature radius sizes at the vertices are both f / 2, the angle of the B point along the tangent radial direction is-55, the curvature radius size is set as f+g, the corresponding spline curve is obtained, then the spline curve is mirrored based on the straight line passing through the center point and the A point of the square sketch as the reference to obtain a projection reference; Then, a projection path is drawn, the projection path is drawn based on the left reference plane, the projection path takes the top and bottom vertices of the square sketch as the endpoints to construct a circular arc with a radius of r1; The projection reference is projected onto the projection path to obtain a projection curve that is curved on the left reference plane, then the projection curve is scanned by a circular contour with a diameter of D1 to obtain a solid structure; The length f direction in the square sketch is determined as the X axis, the height g direction is determined as the Z axis, and the direction perpendicular to the X axis and the Z axis is the Y axis, the solid structure is arrayed five times along the Z axis direction with an array distance of g / 2, the arrayed solid structure is arrayed five times along the X axis direction with an array distance of f, and finally the arrayed solid structure is mirrored along the front reference plane to obtain a Y-shaped bionic bird bone structure monomer; The Y-shaped bionic bird bone structure monomer is arrayed three times along the Y axis direction, and a total of three Y-shaped bionic bird bone structure monomers are included to obtain a Y-shaped bionic bird bone structure.

5. The method for preparing an interpenetrating phase ceramic dental material according to claim 1, characterized in that, The size and the length-width ratio of the two bionic bird bone structure sections in step one are the same.

6. The method for preparing an interpenetrating phase ceramic dental material according to claim 1, characterized in that, The zirconium oxide slurry formula in step two is as follows: 85wt% of 3Y-TZP zirconium oxide powder, 4.5wt% of HDDA, 3.0wt% of PEG400DA, 0.5wt% of a photoinitiator and 2.0wt% of a dispersant are mixed, and a homogeneous and stable slurry with a solid content of 52vol% is prepared by stirring for 40 minutes at 2000rpm under vacuum by a planetary centrifugal stirrer.

7. The method for preparing an interpenetrating phase ceramic dental material according to claim 1, characterized in that, The light curing printing parameters in step two are as follows: Printing is performed by using the parameters of a single layer exposure time of 6 seconds, a bottom layer exposure time of 35 seconds, a single layer thickness of 50μm and a light source light intensity of 15mW / cm²; The printed green body is cleaned by ultrasonic cleaning and dried, then subjected to programmed debinding and sintering to finally obtain a zirconium oxide ceramic as a bionic bird bone mortise and tenon structure.

8. The method for preparing an interpenetrating phase ceramic dental material according to claim 1, characterized in that, The debinding and sintering in step two are specifically as follows: The debinding process is performed in an air atmosphere, and the specific steps are as follows: The temperature is raised to 200℃ at a rate of 1℃ / min and kept for 30 minutes, then the temperature is raised to 500℃ at a rate of 0.5℃ / min and kept for 120 minutes, finally the temperature is raised to 600℃ at a rate of 1℃ / min and kept for 60 minutes, then the furnace is cooled down; The ceramic blank after debinding is placed in a high-temperature sintering furnace for sintering in an air atmosphere, and the specific steps are as follows: Ramp up to 1000 °C at 5 °C / min, no hold, then ramp up to the final sintering temperature of 1500 °C at 2 °C / min and hold at this temperature for 120 min to achieve full densification, finally cool down to below 1000 °C at a rate of 3 °C / min, then furnace cool to room temperature, finally get the biomimetic bird bone mortise and tenon structure with zirconia ceramic as the matrix.

9. The method for preparing an interpenetrating phase ceramic dental material according to claim 1, characterized in that, The specific preparation steps of the in-situ photocrosslinking method for preparing the zirconia-hydrogel interpenetrating phase structure in step three are as follows: Dissolve the solid powder of methacrylated gelatin and the solid powder of the photoinitiator Irgacure 2959 in phosphate buffer as the only solvent, and after the two solutes are matched into a solution, each should reach a concentration of 15% w / v and 0.5% w / v, stir in a 60°C water bath until the two solutes are completely dissolved, then place in a 4°C environment to remove bubbles and use as a precursor solution; After the biomimetic bird bone mortise and tenon structure with zirconia ceramic as the matrix obtained in step two is treated by oxygen plasma, it is completely immersed in the precursor solution and kept in a vacuum environment of -0.1 MPa for 30 minutes for impregnation; After impregnation is complete, the sample is transferred to 365 nm ultraviolet light and irradiated for 75 seconds in a nitrogen atmosphere at a light intensity of 8 mW / cm², causing the methacrylated gelatin to photopolymerize in-situ inside the biomimetic bird bone mortise and tenon structure, forming a stable zirconia-hydrogel interpenetrating phase structure.

10. The method for preparing an interpenetrating phase ceramic dental material according to claim 1, characterized in that, The specific method of preparing a multi-level zirconia-hydrogel biomimetic bird bone structure by sol-gel dip coating in step four is as follows: Sol preparation: mix tetraethyl orthosilicate, ethanol, water and catalyst in a certain proportion, stir and hydrolyze at a certain temperature to form a stable SiO2 sol; Dip coating: completely immerse the zirconia-hydrogel interpenetrating phase structure in the prepared sol and keep it for a period of time to ensure that the inner and outer surfaces are fully infiltrated; Pulling: pull the zirconia-hydrogel interpenetrating phase structure out of the sol at a constant and slow speed to form a uniform liquid film on its surface; Heat treatment: first dry the zirconia-hydrogel interpenetrating phase structure after pulling at 50-100°C, then heat treat at 400-600°C to volatilize the solvent and decompose the organic matter, and finally form an amorphous and dense SiO2-based glass-ceramic coating on the surface of the zirconia-hydrogel interpenetrating phase structure.

Images