CN114560691A

CN114560691A - Antibacterial photocuring 3D printing biological ceramic material and preparation method and application thereof

Info

Publication number: CN114560691A
Application number: CN202210340213.3A
Authority: CN
Inventors: 戴红莲; 李梦; 郑典; 黄孝龙; 伍小沛; 韩颖超
Original assignee: Foshan Xianhu Laboratory
Current assignee: Foshan Xianhu Laboratory
Priority date: 2022-03-30
Filing date: 2022-03-30
Publication date: 2022-05-31
Anticipated expiration: 2042-03-30
Also published as: CN114560691B

Abstract

The invention belongs to the technical field of biological ceramic materials and additive manufacturing, and particularly discloses an antibacterial photocuring 3D printing biological ceramic material and a preparation method and application thereof. The raw materials for preparing the photocuring 3D printing biological ceramic material comprise inorganic powder and photosensitive resin premixed liquid; wherein: the inorganic powder comprises metal oxide powder and calcium phosphate ceramic powder; the metal oxide powder is any one of zinc oxide, copper oxide, and titanium oxide. The biological ceramic material can realize good antibacterial effect and antibacterial durability, so that the survival rate of bacteria is reduced to 29.63%; the mechanical strength of the biological ceramic is improved, and the compressive strength reaches 7.8 MPa; the biological degradable gel also has good biocompatibility and degradability, can be integrated with a body, and is taken out without secondary operation; the method can be suitable for the 3D printing biological ceramic bracket with the three-period extremely-small curved surface structure.

Description

Antibacterial photocuring 3D printing biological ceramic material and preparation method and application thereof

Technical Field

The invention belongs to the technical field of biological ceramic materials and additive manufacturing, and particularly relates to an antibacterial photocuring 3D printing biological ceramic material and a preparation method and application thereof.

Background

3D printing is an additive manufacturing technology, and has an irreplaceable position in clinical bone defect treatment due to the molding advantage of individualization and customization. Three-dimensional photocuring 3D prints as one of common 3D printing technique, has advantages such as shaping speed is fast, the precision is high, can be used for making the great complicated structure of processing degree of difficulty and thin wall hollow structure.

The three-cycle infinitesimal curved surface is a curved surface which periodically changes along the X, Y, Z axis direction in the euclidean space and has zero average curvature. Compared with the traditional structure, the porous structure has uniform stress dispersion and mutual communication, and the overall stability and spatial arrangement are more excellent. Meanwhile, researches show that the average curvature of the trabecular surface of the bone in the human body is zero, and a smooth infinite curved surface formed by three-period extremely small curved surfaces is an ideal geometric structure for simulating the spatial form of the cancellous bone, so that excellent mechanical support and growth environment are provided for bone tissue repair. But at the same time, the three-cycle extremely-small curved surface also puts higher requirements on the performance of the printing material.

The main component of the traditional biological ceramic material is calcium phosphate which is similar to natural bone and has good biocompatibility, and the traditional biological ceramic material is developed as a medical implant and meets the health and sanitation standards of human beings. However, calcium phosphate ceramics do not have obvious antibacterial performance, bone infection may occur during bone grafting, treatment time and difficulty are increased, and pain of patients is increased, and meanwhile, the mechanical property of calcium phosphate ceramics is poor, so that the application of calcium phosphate ceramics in clinical operation is limited.

In the prior art, in order to improve the antibacterial performance of the calcium phosphate bioceramics, inorganic antibacterial agents are added to solve the problem. Although inorganic antibacterial materials have the advantages of broad antibacterial spectrum, good stability, no drug resistance of bacteria, low toxicity and the like, most inorganic antibacterial materials have the defects of poor biocompatibility, relatively weak binding force with biological ceramics and the like, when the inorganic antibacterial materials are used as antibacterial agents, the release time of antibacterial components is relatively short, the long-acting antibacterial effect cannot be achieved, and the mechanical property of the biological ceramics cannot be improved.

Therefore, there is a need to develop an antibacterial bioceramic material with good biocompatibility, slow degradation speed and good mechanical properties.

Disclosure of Invention

The invention provides an antibacterial photocuring 3D printing biological ceramic material, and a preparation method and application thereof, which are used for solving one or more technical problems in the prior art and at least providing a beneficial choice or creation condition.

To overcome the technical problems, the first aspect of the invention provides a photocuring 3D printing bioceramic material.

Specifically, a photocuring 3D printing biological ceramic material, which is prepared from raw materials including inorganic powder and photosensitive resin premix; the inorganic powder comprises metal oxide powder and calcium phosphate ceramic powder; the metal oxide powder is any one of zinc oxide, copper oxide, titanium oxide and tin oxide.

According to the invention, calcium phosphate ceramic powder is used as a substrate material of biological ceramic, and specific metal oxide powder zinc oxide, copper oxide or titanium oxide is selected as an antibacterial agent, so that on one hand, dissolved antibacterial metal ions are utilized to contact bacteria to destroy cell membranes, thereby dissolving out cell contents; on the other hand, the bacteria can lose their biological activity to complete the sterilization process by generating active oxygen to cause oxidative stress and damage to DNA, cell membranes and proteins. Meanwhile, after the antibacterial agent metal oxide is added into the calcium phosphate biological ceramic matrix, the antibacterial agent metal oxide can be used as a sintering aid at high temperature to promote the densification of the biological ceramic, so that the mechanical strength of the biological ceramic is improved. And the calcium phosphate biological ceramic material added with the metal oxide has the advantages of more compact connection among crystal grains, difficult damage to the crystal structure, slow degradation speed and slow ion dissolution speed, and can effectively overcome the defect of short antibacterial time of the existing biological ceramic material. In addition, the metal oxide of the antibacterial agent has good biocompatibility and degradability, and when the metal oxide is used as a biological ceramic material, the metal oxide does not need to be taken out in a secondary operation, so that secondary operation trauma can be avoided, the pain of a patient can be relieved, and the metal oxide of the antibacterial agent has important application value in the field of biomedical engineering.

Preferably, the metal oxide powder is copper oxide.

Preferably, the calcium phosphate ceramic powder is at least one selected from the group consisting of α -tricalcium phosphate, β -tricalcium phosphate, hydroxyapatite, tetracalcium phosphate, octacalcium phosphate, and calcium hydrogen phosphate. The calcium phosphate salts have good biocompatibility, can be directly fused with bones after being implanted into organisms, and are good bioceramic matrixes.

Preferably, the molar ratio of the metal oxide powder to the calcium phosphate salt ceramic powder is (0.5-10): 100, respectively; more preferably, the molar ratio of the metal oxide powder to the calcium phosphate salt ceramic powder is (1-5): 100.

preferably, the mass-to-volume ratio of the inorganic powder to the photosensitive resin premix is (40-80): (20-60) g/mL; more preferably, the mass-to-volume ratio of the inorganic powder to the photosensitive resin premix is (60-70): (30-40) g/mL.

Preferably, the photosensitive resin premix includes a photosensitive resin, a dispersant and a photoinitiator.

Preferably, the volume ratio of the photoinitiator to the photosensitive resin is (0.5-3): (20-80).

Preferably, the addition amount of the dispersant is 0.25-5 wt% of the inorganic powder.

Preferably, the photosensitive resin is at least one selected from the group consisting of tripropylene glycol diacrylate, vinyl acetate, butyl acrylate, 1, 6-hexanediol diacrylate, tripropylene glycol diacrylate, and trimethylolpropane triacrylate.

Preferably, the dispersant is at least one selected from the group consisting of DISPERBYK-110, DISPERBYK-111, DISPERBYK180, DISPERBYK2159, and phosphate ester S18.

Preferably, the photoinitiator is at least one selected from the group consisting of photoinitiator 184D, 1-hydroxycyclohexyl phenyl ketone, phenyl bis (2,4, 6-trimethylbenzoyl) phosphine oxide, 2,4, 6-trimethylbenzoyl-diphenyl phosphine oxide.

Preferably, the particle size of the calcium phosphate salt ceramic powder is 100-1000 nm.

Preferably, the particle size of the metal oxide powder is 10 to 100 μm.

The second aspect of the invention provides a preparation method of a photocuring 3D printing biological ceramic material.

Specifically, the preparation method of the photocuring 3D printing biological ceramic material comprises the following steps:

(1) adding inorganic powder into the photosensitive resin premix and mixing to obtain ceramic slurry;

(2) 3D printing is carried out on the ceramic slurry, and then layered photocuring forming is carried out to obtain a ceramic biscuit;

(3) and degreasing and sintering the ceramic biscuit to obtain the photocuring 3D printing biological ceramic material.

Preferably, in the step (1), the mixing is performed under the condition of ball milling at normal temperature and normal pressure to uniformly disperse the components.

Preferably, in step (2), before the 3D printing, the method further includes the following steps: the method comprises the steps of designing a TPMS-gyroid (three-cycle extremely-small curved surface-spiral) three-dimensional through structure of the porous ceramic support by adopting three-dimensional modeling software, creating a model, adjusting printing parameters such as the wall thickness porosity of the structure by utilizing a Grasshopper (a visual programming language) parameterized plug-in, storing the printing parameters as an STL (standard template library) format file, and guiding the file into a three-dimensional photocuring 3D printer.

Preferably, in step (2), the parameters of 3D printing are: the laser power is 10-1000mW, the laser scanning speed is 0.5-80m/s, and the spot diameter is 10-150 μm.

Preferably, in the step (2), the thickness of the delamination is 25 to 200 μm.

Preferably, in the step (2), the light source wavelength of the photocuring molding is 350-450 nm.

Preferably, step (3) further comprises the steps of immersing the ceramic biscuit in a cleaning solution before degreasing, performing ultrasonic cleaning to remove uncured slurry, and then cleaning with deionized water and drying.

Preferably, in the step (3), the temperature for degreasing and sintering is 900-.

Preferably, in the step (3), the temperature system for degreasing and sintering is as follows: firstly, heating from room temperature to 700 ℃ at the heating rate of 1-10 ℃/min, and keeping the temperature for 1.5-2.5 h; then heating to 900-; and finally naturally cooling to room temperature.

The third aspect of the invention provides an application of the photocuring 3D printing biological ceramic material.

Concretely, a biological ceramic support comprises the photocuring 3D printing biological ceramic material, and the biological ceramic support has a three-cycle extremely-small curved surface structure.

Preferably, the three-period extremely-small curved surface structure is designed through a Rhino modeling software, and the porosity of the whole structure is controlled through regulating and controlling the wall thickness and the number of structural units.

Preferably, the biological ceramic scaffold comprises multilevel pores, the size of the multilevel pores is 300-1000 μm, and the porosity is 20-80%.

Compared with the prior art, the technical scheme of the invention at least has the following technical effects or advantages:

according to the invention, specific metal oxide powder zinc oxide, copper oxide, titanium oxide or tin oxide is added into the calcium phosphate biological ceramic matrix as an antibacterial agent, so that a good antibacterial effect can be realized, the survival rate of bacteria is reduced to 29.63%, and the antibacterial biological ceramic matrix has good antibacterial durability; meanwhile, the metal oxide can be used as a sintering aid at high temperature to promote the densification of the biological ceramic, thereby improving the mechanical strength of the biological ceramic, realizing that the compressive strength reaches 7.8MPa, and greatly improving the compressive strength compared with the single calcium phosphate biological ceramic. The antibacterial biological ceramic material also has good biocompatibility and degradability, can be integrated with an organism, and does not need to be taken out in a secondary operation.

The biological ceramic material disclosed by the invention can be suitable for a three-dimensional photocuring 3D printing forming technology, compared with other forming modes, the photocuring 3D printing has the advantages of high forming speed, high precision and the like, and can meet the bone grafting requirement of special parts. The manufacturing of a three-dimensional through TPMS-gyroid bionic porous structure similar to a cancellous bone structure can be realized, and meanwhile, the porosity can be parametrically controlled within the range of 10-90% according to the porosity range of the cancellous bone of a human body, so that the transportation of nutrient substances and the transportation of metabolic waste are effectively promoted, the bone regeneration is enhanced, and the biocompatibility of the biological ceramic material is further improved.

Drawings

FIG. 1 is a three-dimensional modeling design drawing of a bioceramic scaffold according to example 1 of the present invention;

FIG. 2 is a bisque-fired body of a bioceramic scaffold according to example 1 of the present invention;

FIG. 3 is the bio-ceramic scaffold after degreasing and sintering according to example 1 of the present invention;

FIG. 4 is an XRD plot of the bioceramic scaffolds of examples 3-5 and comparative example 1 of the present invention;

fig. 5 is SEM images of the bioceramic scaffolds of inventive examples 3-5 and comparative example 1.

Detailed Description

The present invention is described in detail below by way of examples to facilitate understanding of the present invention by those skilled in the art, and it is to be specifically noted that the examples are provided only for the purpose of further illustrating the present invention and are not to be construed as limiting the scope of the present invention.

Example 1

A photocuring 3D printing biological ceramic material is prepared from inorganic powder (alpha-tricalcium phosphate powder and zinc oxide powder) and photosensitive resin premix (photosensitive resin tripropylene glycol diacrylate and butyl acrylate, dispersant DISPERBYK-110 and photoinitiator 2,4, 6-trimethylbenzoyl-diphenylphosphine oxide). Wherein: the mol ratio of the zinc oxide powder to the alpha-tricalcium phosphate powder is 1: 100; the volume ratio of 2,4, 6-trimethylbenzoyl-diphenylphosphine oxide to the photosensitive resin is 1: 20; the volume ratio of the tripropylene glycol diacrylate to the butyl acrylate is 1: 1; the addition amount of the dispersant DISPERBYK-110 is 0.5 wt% of the inorganic powder; the mass volume ratio of the inorganic powder to the photosensitive resin premix is 60: 40 g/mL; the grain diameter of the alpha-tricalcium phosphate powder is 200 nm; the particle size of the zinc oxide powder was 20 μm.

A preparation method of a photocuring 3D printing biological ceramic material comprises the following steps:

(1) firstly adding DISPERBYK-110 into tripropylene glycol diacrylate and butyl acrylate, then adding 2,4, 6-trimethylbenzoyl-diphenyl phosphine oxide, and uniformly mixing in a planetary ball mill to obtain a photosensitive resin premix;

(2) adding alpha-tricalcium phosphate powder and zinc oxide powder into the photosensitive resin premix prepared in the step (1) for three times (the mass of each time is the same), and performing ball milling for 2 hours at the rotating speed of 200r/min, 250r/min and 300/min at normal temperature and normal pressure in sequence to uniformly disperse the components to obtain ceramic slurry;

(3) designing a TPMS-gyroid three-dimensional through structure of the porous ceramic support by adopting a Rhino modeling software, creating a model (shown in figure 1), adjusting printing parameters such as the wall thickness porosity of the structure by utilizing a Grasshopper parameterized plug-in, storing the printing parameters as an STL format file, and guiding the STL format file into a three-dimensional photocuring 3D printer;

(4) pouring the ceramic slurry prepared in the step (2) into a particle groove of a three-dimensional photocuring 3D printer, and adjusting printing parameters of the photocuring 3D printer to solidify the ceramic slurry layer by layer, wherein: the parameters for 3D printing are: the wavelength of a light source for photocuring molding is 355 nm; the laser power is 500mW, the laser scanning speed is 30m/s, and the spot diameter is 20 μm; the thickness of the layers was 100 μm; obtaining a ceramic biscuit (as shown in figure 2);

(5) immersing the ceramic biscuit prepared in the step (4) in a cleaning solution, ultrasonically cleaning the uncured ceramic slurry, cleaning and drying the ceramic slurry by using deionized water, and then placing the ceramic biscuit in a muffle furnace for degreasing and sintering, wherein: the temperature system of degreasing and sintering is as follows: firstly, heating from room temperature to 500 ℃ at the heating rate of 5 ℃/min, and keeping the temperature for 2 h; then heating to 1100 ℃ at the heating rate of 5 ℃/min, and preserving heat for 2 h; finally, the biological ceramic scaffold of the present example was prepared by natural cooling to room temperature (as shown in fig. 3).

As can be seen from FIGS. 1 to 3, the ceramic biscuit (FIG. 2) after 3D printing and the biological ceramic scaffold (FIG. 3) after sintering and de-sintering are consistent with the model (FIG. 1) structure of the porous ceramic scaffold designed by the three-dimensional modeling software, and the printed pore structures are communicated completely and clearly, the forming and sintering effects are good, and no pore blockage, delamination or damage phenomenon is found.

Example 2

A photocuring 3D printing biological ceramic material is prepared from inorganic powder (beta-tricalcium phosphate powder and titanium oxide powder) and photosensitive resin premix (photosensitive resin tripropylene glycol diacrylate, trimethylolpropane triacrylate, dispersant phosphate S18 and photoinitiator 2,4, 6-trimethylbenzoyl-diphenylphosphine oxide). Wherein: the molar ratio of the titanium oxide powder to the beta-tricalcium phosphate powder is 3: 100, respectively; the volume ratio of 2,4, 6-trimethylbenzoyl-diphenylphosphine oxide to the photosensitive resin is 1: 30, of a nitrogen-containing gas; the volume ratio of the tripropylene glycol diacrylate to the trimethylolpropane triacrylate is 1: 3; the addition amount of the dispersant phosphate S18 is 1 wt% of the inorganic powder; the mass volume ratio of the inorganic powder to the photosensitive resin premix is 70: 30 g/mL; the grain diameter of the alpha-tricalcium phosphate powder is 300 nm; the particle size of the zinc oxide powder was 30 μm.

(1) adding phosphate S18 into tripropylene glycol diacrylate and trimethylolpropane triacrylate, adding 2,4, 6-trimethylbenzoyl-diphenyl phosphine oxide, and uniformly mixing in a planetary ball mill to obtain a photosensitive resin premix;

(2) adding beta-tricalcium phosphate powder and titanium oxide powder into the photosensitive resin premix prepared in the step (1) for three times (the mass of each time is the same), and performing ball milling for 2 hours at the rotating speed of 200r/min, 250r/min and 250/min at normal temperature and normal pressure in sequence to uniformly disperse the components to obtain ceramic slurry;

(3) designing a TPMS-gyroid three-dimensional through structure of the porous ceramic support by adopting a Rhino modeling software, creating a model, adjusting printing parameters such as wall thickness porosity and the like of the structure by utilizing a Grasshopper parameterized plug-in, storing the printing parameters as an STL format file, and guiding the STL format file into a three-dimensional photocuring 3D printer;

(4) pouring the ceramic slurry prepared in the step (2) into a particle groove of a three-dimensional photocuring 3D printer, and adjusting printing parameters of the photocuring 3D printer to solidify the ceramic slurry layer by layer, wherein: the parameters for 3D printing are: the wavelength of a light source for photocuring molding is 355 nm; the laser power is 200mW, the laser scanning speed is 30m/s, and the spot diameter is 50 μm; the thickness of the delamination was 50 μm; obtaining a ceramic biscuit;

(5) immersing the ceramic biscuit prepared in the step (4) in a cleaning solution, ultrasonically cleaning the uncured ceramic slurry, cleaning and drying the ceramic slurry by using deionized water, and then placing the ceramic biscuit in a muffle furnace for degreasing and sintering, wherein: the temperature system of degreasing and sintering is as follows: firstly, heating from room temperature to 600 ℃ at the heating rate of 2 ℃/min, and keeping the temperature for 2 h; then heating to 900 ℃ at the heating rate of 1 ℃/min, and preserving heat for 2 h; finally, naturally cooling to room temperature to obtain the biological ceramic scaffold of the embodiment.

Example 3

A photocuring 3D printing biological ceramic material is prepared from inorganic powder (hydroxyapatite powder and copper oxide powder) and photosensitive resin premix (photosensitive resin tripropylene glycol diacrylate and 1, 6-hexanediol diacrylate, dispersing agent DISPERBYK-111 and DISPERBYK180, and photoinitiator phenyl bis (2,4, 6-trimethylbenzoyl) phosphine oxide). Wherein: the molar ratio of the copper oxide powder to the hydroxyapatite powder is 1: 100, respectively; the volume ratio of the phenylbis (2,4, 6-trimethylbenzoyl) phosphine oxide to the photosensitive resin is 0.5: 20; the volume ratio of the tripropylene glycol diacrylate to the 1, 6-hexanediol diacrylate is 1: 3; the addition amount of the dispersing agent is 2 wt% of the inorganic powder; the mass ratio of DISPERBYK-111 to DISPERBYK180 is 1: 1; the mass volume ratio of the inorganic powder to the photosensitive resin premixed liquid is 70: 30 g/mL; the grain diameter of the alpha-tricalcium phosphate powder is 300 nm; the particle size of the zinc oxide powder was 40 μm.

(1) adding DISPERBYK-111 and DISPERBYK180 into tripropylene glycol diacrylate and 1, 6-hexanediol diacrylate, adding phenyl bis (2,4, 6-trimethylbenzoyl) phosphine oxide, and uniformly mixing in a planetary ball mill to obtain a photosensitive resin premix;

(2) adding hydroxyapatite powder and zinc oxide powder into the photosensitive resin premix prepared in the step (1) for three times (the mass of each time is the same), and performing ball milling for 2 hours at the rotating speed of 200r/min, 250r/min and 250/min at normal temperature and normal pressure in sequence to uniformly disperse the components to obtain ceramic slurry;

(4) pouring the ceramic slurry prepared in the step (2) into a particle groove of a three-dimensional photocuring 3D printer, and adjusting printing parameters of the photocuring 3D printer to solidify the ceramic slurry layer by layer, wherein: the parameters for 3D printing are: the wavelength of a light source for photocuring molding is 405 nm; the laser power is 5mW, the laser scanning speed is 1m/s, and the spot diameter is 50 μm; the thickness of the delamination was 25 μm; obtaining a ceramic biscuit;

(5) immersing the ceramic biscuit prepared in the step (4) in a cleaning solution, ultrasonically cleaning the uncured ceramic slurry, cleaning and drying the ceramic slurry by using deionized water, and then placing the ceramic biscuit in a muffle furnace for degreasing and sintering, wherein: the temperature system of degreasing and sintering is as follows: firstly, heating from room temperature to 700 ℃ at the heating rate of 1 ℃/min, and keeping the temperature for 2 h; then heating to 1100 ℃ at the heating rate of 1 ℃/min, and preserving heat for 2 h; finally, naturally cooling to room temperature to obtain the biological ceramic scaffold of the embodiment.

Example 4

Example 4 differs from example 3 in that the molar ratio of the copper oxide powder to the hydroxyapatite powder in the photocurable 3D printing bioceramic material of example 4 is 3: 100, other preparation raw materials and addition amounts, and the preparation method of the photocuring 3D printing bioceramic material are the same as those in example 3.

Example 5

Example 5 differs from example 3 in that the molar ratio of the copper oxide powder to the hydroxyapatite powder in the photocurable 3D printing bioceramic material of example 5 is 5: 100, other preparation raw materials and addition amounts, and the preparation method of the photocuring 3D printing bioceramic material are the same as those in example 3.

Comparative example 1

The difference between the comparative example 1 (control group) and the example 3 is that the metal oxide powder is not added to the photo-curing 3D printing biological ceramic material in the comparative example 1, and other preparation raw materials and addition amount, and the preparation method of the photo-curing 3D printing biological ceramic material are the same as those in the example 3.

Performance testing

XRD analysis

XRD (X-ray diffraction) detection analysis was performed on the bioceramic scaffold samples prepared in examples 3-5 and comparative example 1, and the detection results are shown in FIG. 4, wherein the abscissa 2theta represents the angle 2theta and the ordinate intensity represents the intensity in FIG. 4. As can be seen from fig. 4, in examples 3 to 5 in which the metal oxide copper oxide was added, the original calcium phosphate phase was maintained, but the peak position was slightly shifted from that in comparative example 1 in which no copper oxide powder was added, indicating that the metal ion entered the crystal lattice of the calcium ion, but no new phase was formed.

2. Microstructure

The bioceramic scaffold samples prepared in examples 3-5 and comparative example 1 were subjected to SEM microstructure testing, the results of which are shown in fig. 5, wherein: fig. 5A is a sample of the bioceramic scaffold prepared in comparative example 1, and fig. 5B, 5C and 5D show samples of the bioceramic scaffolds prepared in examples 3, 4 and 5, respectively. As can be seen from FIG. 5, as the amount of the metal oxide added increases, the degree of densification of the bioceramic also increases, indicating that the metal oxide functions as a sintering aid.

3. Mechanical properties

The bio-ceramic scaffolds prepared in examples 1-5 and comparative example 1 were tested for compressive strength according to the test standard GB/T4740-1999, and the test results are shown in Table 1.

Table 1: table for comparing compressive strength of bioceramic scaffolds of each example and comparative example

Sample (I)	Example 1	Example 2	Example 3	Example 4	Example 5	Comparative example 1
							Compressive strength (MPa)	1.5	2	2.8	4.5	7.8	0.5

As is clear from Table 1, examples 1 to 5 in which a metal oxide, copper oxide, titanium oxide or zinc oxide was added to a bioceramic matrix all had better compressive strength than comparative example 1 in which no metal oxide was added, and particularly example 5 in which copper oxide was added had compressive strength 15.6 times that of comparative example 1. The metal oxide of the invention can effectively improve the mechanical strength of the biological ceramic bracket.

4. Antibacterial property

The bio-ceramic scaffolds prepared in examples 1-5 and comparative example 1 were tested for bacterial survival rate according to test standard JC/T897-2014, and the test results are shown in Table 2.

Table 2: antibacterial property comparison table of bioceramic scaffold of each example and comparative example

Sample (I)	Example 1	Example 2	Example 3	Example 4	Example 5	Comparative example 1
							Bacterial survival rate (%)	91.33	82.51	77.78	29.63	56.79	92.59

As can be seen from Table 2, examples 1 to 5, in which copper oxide, titanium oxide or zinc oxide, which is a metal oxide, was added to the bioceramic matrix, had better antibacterial performance than comparative example 1, in which no metal oxide was added; the antibacterial performance of the examples 3-5 added with copper oxide is obviously better than that of the examples 1-2 added with titanium oxide and zinc oxide, and the antibacterial effect of the example 4 added with 3 percent is optimal. The metal oxides of the present invention all have certain antibacterial properties.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are intended to be within the scope of the invention.

Claims

1. The photocuring 3D printing biological ceramic material is characterized in that raw materials for preparing the photocuring 3D printing biological ceramic material comprise inorganic powder and photosensitive resin premixed liquid; the inorganic powder comprises metal oxide powder and calcium phosphate ceramic powder; the metal oxide powder is any one of zinc oxide, copper oxide and titanium oxide.

2. The photocurable 3D printing bioceramic material of claim 1, wherein the calcium phosphate salt ceramic powder is selected from at least one of α -tricalcium phosphate, β -tricalcium phosphate, hydroxyapatite, tetracalcium phosphate, octacalcium phosphate, and calcium hydrogen phosphate.

3. The photocuring 3D printing bioceramic material of claim 1, wherein the molar ratio of the metal oxide powder to the calcium phosphate salt ceramic powder is (0.5-10): 100, respectively; the mass volume ratio of the inorganic powder to the photosensitive resin premix is (40-80): (20-60) g/mL.

4. The photocuring 3D printing bioceramic material of claim 1, wherein the photosensitive resin premix comprises a photosensitive resin, a dispersant and a photoinitiator; the volume ratio of the photoinitiator to the photosensitive resin is (0.5-3): (20-80); the addition amount of the dispersant is 0.25 to 5 weight percent of the inorganic powder.

5. The photocurable 3D printing bioceramic material of claim 4, wherein the photosensitive resin is selected from at least one of tripropylene glycol diacrylate, vinyl acetate, butyl acrylate, 1, 6-hexanediol diacrylate, tripropylene glycol diacrylate, trimethylolpropane triacrylate;

the dispersant is at least one selected from DISPERBYK-110, DISPERBYK-111, DISPERBYK180, DISPERBYK2159 and phosphate S18;

the photoinitiator is at least one selected from the group consisting of photoinitiator 184D, 1-hydroxycyclohexyl phenyl ketone, phenyl bis (2,4, 6-trimethylbenzoyl) phosphine oxide, and 2,4, 6-trimethylbenzoyl-diphenyl phosphine oxide.

6. The photocuring 3D printing biological ceramic material as claimed in claim 1, wherein the particle size of the calcium phosphate salt ceramic powder is 100-1000 nm; the particle size of the metal oxide powder is 10-100 μm.

7. The preparation method of the photocuring 3D printing bioceramic material of any of claims 1-6, comprising the steps of:

8. The preparation method of the photocuring 3D printing biological ceramic material as claimed in claim 7, wherein in the step (2), the parameters of 3D printing are as follows: the laser power is 10-1000mW, the laser scanning speed is 0.5-80m/s, and the spot diameter is 10-150 μm; the thickness of the layering is 25-200 μm; the wavelength of the light source for photocuring molding is 350-450 nm;

in the step (3), the temperature for degreasing and sintering is 900-1100 ℃.

9. A bioceramic scaffold comprising the photocurable 3D-printed bioceramic material of any one of claims 1 to 6, the bioceramic scaffold having a three-cycle minimal-curvature structure.

10. The bioceramic scaffold according to claim 9, wherein the bioceramic scaffold comprises multi-stage pores, the size of the multi-stage pores is 300-1000 μm, and the porosity is 20-80%.