阅读说明：本技术 纯钛牙种植体及其制作方法 (Pure titanium dental implant and manufacturing method thereof ) 是由 许志强 贺于奇 于 2019-11-19 设计创作，主要内容包括：一种纯钛牙种植体,其要点在于在纯钛牙种植体表面制有若干微米级沟槽,在沟槽中制有垂直于牙种植体中心轴的纳米管。沟槽的宽度为50μm,深度10μm,相邻沟槽的间距为50-53μm。本发明先在牙种植体表面制作中沟槽,再在沟槽上制作纳米管,使纳米管的顶部表面为斜面,与骨组织界面和软组织界面接触面大,微米级的沟槽可以诱导骨组织细胞和软组织细胞更好地顺着沟槽生长,纳米管也有利于蛋白、氧气和养份的吸附。沟槽的尺寸刚好略小于未伸展的骨髓基质干细胞和牙龈成纤维细胞,保证细胞不会掉落于沟槽之中,而使得细胞能顺着沟槽生长。可以促进牙龈成纤维细胞的增殖和软组织封闭相关基因的表达,即达到了兼具成骨和软组织封闭的效果。(The pure titanium dental implant is characterized in that a plurality of micron-sized grooves are formed on the surface of the pure titanium dental implant, and nanotubes vertical to the central axis of the dental implant are formed in the grooves. The width of the groove is 50 μm, the depth is 10 μm, and the distance between adjacent grooves is 50-53 μm. The invention firstly makes a middle groove on the surface of the dental implant, and then makes a nano tube on the groove, so that the top surface of the nano tube is an inclined surface, the contact surface with a bone tissue interface and a soft tissue interface is large, the micron-sized groove can induce bone tissue cells and soft tissue cells to grow along the groove better, and the nano tube is also beneficial to the adsorption of protein, oxygen and nutrients. The size of the groove is just slightly smaller than the unstretched bone marrow stromal stem cells and gingival fibroblasts, so that the cells are prevented from falling into the groove and can grow along the groove. Can promote the proliferation of gingival fibroblasts and the expression of genes related to soft tissue sealing, and achieves the effects of osteogenesis and soft tissue sealing.)

1. A pure titanium dental implant is characterized in that a plurality of micron-sized grooves are formed on the surface of the pure titanium dental implant, and nanotubes vertical to the central axis of the dental implant are formed in the grooves.

2. The pure titanium dental implant of claim 1, wherein the width of the groove is 50 μm and the depth is 5 μm.

3. The pure titanium dental implant of claim 1, wherein the spacing between adjacent micron-sized flutes is 50-53 μm.

4. The pure titanium dental implant of claim 1, wherein the nanotubes are titanium dioxide nanotubes.

5. The pure titanium dental implant of any one of claims 1 or 4, wherein the nano tube diameter is 100 ± 15nm, the tube wall thickness is 10 ± 2nm, and the tube length is 2.2 ± 0.2 μm.

6. The pure titanium dental implant of claims 1-3, wherein the micron-sized grooves on the surface of the dental implant are vertical longitudinal grooves.

7. A method for manufacturing a pure titanium dental implant with osteogenesis and soft tissue sealing is characterized in that micron-sized grooves are prepared on the surface of the pure titanium dental implant, the pure titanium dental implant is cleaned, and then the dental implant with the micron-sized grooves is subjected to an electrochemical anodic oxidation method to prepare titanium dioxide nanotubes.

8. According to claimThe method for manufacturing the pure titanium dental implant with osteogenesis and soft tissue sealing functions as claimed in claim 7, wherein the equipment used for preparing the micron-sized groove on the surface of the pure titanium dental implant is an inductively coupled plasma etching machine, after the preparation is completed, acetone and deionized water are respectively used for ultrasonic cleaning for 10min to remove oil, and 4wt% of HF-5mol/L HNO is used₃After the solution is chemically etched for 10s, the substrate is washed by deionized water and dried for later use.

9. The method for preparing a pure titanium dental implant with osteogenesis and soft tissue sealing functions as claimed in claim 8, wherein the electrochemical anodic oxidation method for preparing titanium dioxide nanotubes is performed in a conventional two-electrode system electrochemical cell under water bath conditions, the dental implant prepared for use after pretreatment is used as an anode, a cathode is made of platinum, the shape of the cathode is a hollow cylinder, the inner surface of the cathode has the same taper as that of the implant, the upper surface and the lower surface of the cathode are open, the cathode is sleeved outside the dental implant and keeps a 1cm distance with the surface of the implant, and the electrolyte is 0.50 wt% of NH₄F+10vol% H₂And (3) the whole anodic oxidation process is accompanied with the stirring of a magnetic stirrer, the electrolyte solution is controlled to keep the environmental temperature at 30 +/-2 ℃, a direct-current stabilized power supply provides an anodic oxidation power supply, then the annealing treatment is carried out for 2 hours at 450 ℃, and the deionized water is washed clean.

10. The method for preparing a pure titanium dental implant with osteogenesis and soft tissue sealing functions as claimed in claim 9, wherein in the process of preparing the titanium dioxide nanotube, the anodic oxidation is performed for 3 hours under 30v voltage to obtain a nano tube with a diameter of 100 ± 15nm, a thickness of 10 ± 2nm and a length of 2.2 ± 0.2 μm.

Technical Field

The invention belongs to a dental implant, and particularly relates to a pure titanium dental implant and a preparation method thereof.

Background

With the development of oral implant technology and biomaterials, the implantation of titanium implants in the jaw bone has become a routine method for repairing tooth loss at present. The structure is shown in figure 1, the whole body of the cervical vertebra cervical. The implant is implanted into the oral cavity as a substitute for natural teeth, which forms two interfaces with the tissues in the oral cavity: one is the implant-bone tissue interface and the other is the implant-soft tissue interface. Not only does the success of the implantation require a good osseointegration to be established, but the formation of a good soft tissue seal of the implant collar with the surrounding soft tissue is also decisive. However, the existing pure titanium cannot form good osteogenesis effect and soft tissue sealing due to the biological inertia, so that the preparation of the bifunctional coating with the osteogenesis and soft tissue sealing effects on the surface of the titanium implant has very important significance.

The surface of the titanium implant clinically applied at present is in a micron roughness level. With the rapid development of nanotechnology, the knowledge of the microstructure of the implant surface has also entered the nanometer era. The components of natural bone tissue and gingival tissue and extracellular matrix for regulating and controlling biological behaviors of bone cells and gingival cells are all nano-sized, so that the nano-structured material has a huge application prospect in the field of dental implants from the perspective of bionics.

The designer is dedicated to research and application of dental implants for a long time, and has applied for 'a nano medicine carrying device with osteogenesis and antibiosis and a preparation method thereof', the patent application number is 2016107351436, a titanium dioxide nanotube is directly processed on the surface of pure titanium, and a loading layer of polylactic glycolic acid and octenidine hydrochloride is manufactured in the titanium dioxide nanotube, so that medicine carrying is realized, related infection of the titanium implant is reduced or even avoided, and the long-term success rate of the implant is improved. But the osteogenesis effect and the soft tissue sealing effect are not ideal, and the bonding force of the external load layer and the titanium substrate is weak, so that the external load layer is easy to strip.

Disclosure of Invention

The invention aims to overcome the defects of unsatisfactory bone formation effect and soft tissue sealing effect in the conventional dental implantation process, and provides a pure titanium dental implant with better bone formation effect and soft tissue sealing effect to improve the long-term success rate of the implant.

The technical scheme adopted by the invention is that the pure titanium dental implant is characterized in that a plurality of micron-sized grooves are formed on the surface of the pure titanium dental implant, and nanotubes vertical to the central axis of the dental implant are formed in the grooves.

The invention firstly makes a middle groove on the surface of the dental implant, then makes a nano tube on the groove, and the nano tube has no load layer, thus having no defect of stripping.

The micron-sized trenches have a width of 50 μm and a depth of 10 μm. The spacing between adjacent micron-sized grooves is 50-53 μm. The size of the groove is just slightly smaller than the unstretched bone marrow stromal stem cells and gingival fibroblasts, so that the cells are prevented from falling into the groove and can grow along the groove. The grooves are distributed at intervals in parallel, which is beneficial to inducing cells to be regularly arranged along the parallel trend of the grooves. The grooves are uniformly distributed at equal intervals, so that the deformation stimulation of the cell to the cytoskeleton caused by the crest of the groove with the same width is favorably realized, and the cells are kept in a relatively consistent biological state after being subjected to the morphological action.

The nanotubes are titanium dioxide nanotubes. The diameter of the nanometer tube is 100 plus or minus 15nm, the thickness of the tube wall is 10 plus or minus 2nm, and the length of the tube is 2.2 plus or minus 0.2 mu m. The tube diameter nanotube can adsorb more fibronectin and promote cell adhesion and extension, not only can support the proliferation of bone marrow mesenchymal stem cells and promote the expression of osteogenesis related genes, but also can promote the proliferation of gingival fibroblasts and the expression of soft tissue sealing related genes, and achieves the effect of both osteogenesis and soft tissue sealing.

The micron-sized groove on the surface of the dental implant is a vertical groove. The longitudinal vertical groove in the same direction as the central axis of the dental implant can not damage the thread structure of the dental implant, thereby ensuring the good initial stability and stress distribution of the implant. Through the contact induction effect, the induction cells are favorably arranged regularly along the parallel trend of the groove, and the proliferation and the activity of the mesenchymal stem cells and the fibroblasts of the cells are promoted.

The micron-sized groove on the surface of the dental implant is a circular groove or a continuous spiral groove which takes the central axis of the dental implant as the center.

The manufacturing method of the invention comprises the following steps: preparing micron-sized grooves on the surface of the pure titanium dental implant, cleaning, and then preparing the titanium dioxide nanotube by performing an electrochemical anodic oxidation method on the dental implant with the micron-sized grooves.

The equipment used for preparing the micron-sized groove on the surface of the pure titanium dental implant is an inductively coupled plasma etching machine, after the preparation is finished, acetone and deionized water are respectively used for ultrasonic cleaning for 10min to remove oil, and 4wt% of HF-5mol/LHNO₃After the solution is chemically etched for 10s, the substrate is washed by deionized water and dried for later use.

The surface of the pure titanium dental implant is provided with the same-direction micron-scale groove shape by an inductively coupled plasma etching machine.

The preparation of the titanium dioxide nanotube by the electrochemical anodic oxidation method is carried out in a conventional two-electrode system electrochemical cell under the water bath condition, the pretreated dental implant for later use is an anode, a cathode is made of a platinum sheet and is in a hollow cylinder shape, the inner surface of the cathode has the same taper as that of the implant, the upper surface and the lower surface of the cathode are open, the cathode is sleeved outside the dental implant and keeps a 1cm distance with the surface of the implant, and an electrolyte is 0.50 wt% NH₄F+10vol％H₂And (3) the whole anodic oxidation process is accompanied with the stirring of a magnetic stirrer, the electrolyte solution is controlled to keep the environmental temperature at 30 +/-2 ℃, a direct-current stabilized power supply provides an anodic oxidation power supply, then the annealing treatment is carried out for 2 hours at 450 ℃, and the deionized water is washed clean.

In the process of preparing the titanium dioxide nanotube, anodizing for 3 hours under the voltage of 30v to prepare the titanium dioxide nanotube with the diameter of 100 +/-15 nm, the wall of 10 +/-2 nm and the length of 2.2 +/-0.2 mu m.

The electrolyte used in the invention is an organic electrolyte system containing fluorine ions, the organic solvent has high viscosity and high dielectric constant, the corrosion effect of the fluorine ions on titanium dioxide is weaker, and the time for the reaction to reach balance is longer, so that the nanotube prepared in the system has smooth surface and uniform aperture. The prepared titanium dioxide nanotube is directly connected with the metal titanium conductive substrate by a Schottky barrier, which is different from the modification of an external coating on the titanium surface, the titanium dioxide nanotube is firmly combined and is not easy to fall off, and the titanium dioxide nanotube presents extremely high orderliness and extremely low agglomeration degree.

The prepared nanotube is not only beneficial to the adsorption of protein, oxygen and nutrients, but also can induce the pseudopodia and pseudopodium of cells to crawl towards the nanotube, thereby promoting the proliferation and differentiation of bone marrow stromal stem cells and gingival fibroblasts.

The titanium dioxide nanotube is prepared by an electrochemical anodic oxidation method, and the method has low cost and is simple and convenient. Before anodic oxidation, an inductive coupling plasma etching machine is used for preparing the same-direction micron-scale groove shape. Then the diameter of the nanotube can be controlled more accurately by controlling the voltage of anodic oxidation and the oxidation time.

The invention firstly makes a middle groove on the surface of the dental implant, and then makes a nano tube on the groove, so that the top surface of the nano tube is an inclined surface, the contact surface with a bone tissue interface and a soft tissue interface is large, the micron-sized groove can induce bone tissue cells and soft tissue cells to grow along the groove better, and the nano tube is also beneficial to the adsorption of protein, oxygen and nutrients. The size of the groove is just slightly smaller than the unstretched bone marrow stromal stem cells and gingival fibroblasts, so that the cells are prevented from falling into the groove and can grow along the groove. The grooves are distributed at intervals in parallel, which is beneficial to inducing cells to be regularly arranged along the parallel trend of the grooves. The grooves are uniformly distributed at equal intervals, so that the deformation stimulation of the cell to the cytoskeleton caused by the crest of the groove with the same width is favorably realized, and the cells are kept in a relatively consistent biological state after being subjected to the morphological action. The selected nanotubes with proper tube diameters can adsorb more fibronectin and promote cell adhesion and extension, can support the proliferation of bone marrow mesenchymal stem cells and promote the expression of osteogenesis related genes, can promote the proliferation of gingival fibroblasts and the expression of soft tissue sealing related genes, and achieves the effect of osteogenesis and soft tissue sealing.

Drawings

FIG. 1 is a schematic structural view of a conventional dental implant;

FIG. 2 is a schematic view of a dental implant according to the present invention;

FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2;

FIG. 4 is an enlarged view at D of FIG. 3 (with dashed lines indicating portions of the nanotubes);

FIG. 5 is an enlarged view of a nanotube in a micro-trench;

FIG. 6 is a partial enlarged view of FIG. 5 taken along line B;

FIG. 7 is a schematic diagram of the preparation of titanium dioxide nanotubes;

wherein: 1 dental implant, 2 grooves, 3 nanotubes, 4 cathodes and 5 magnetic stirrers.

Detailed Description

The following detailed description of the invention, taken in conjunction with the accompanying drawings, will provide those skilled in the art with a better understanding of the invention, and is not intended to limit the invention in any way.

As shown in fig. 2-7, the schematic structures are illustrated because the sizes of the structures are different by a factor of 1000. A pure titanium dental implant 1 is provided with a plurality of micron-sized grooves 2 on the surface of the pure titanium dental implant, the grooves are uniformly distributed along the circumferential surface of the implant, the longitudinal height from the top surface to the end point of a root thread, nano tubes 3 vertical to the central axis of the dental implant are arranged in the grooves, and the nano tubes are uniformly and densely distributed on the surface of the dental implant.

The surface of the pure titanium dental implant is provided with the same-direction micron-scale groove shape by an inductively coupled plasma etching machine.

The micron-sized trenches have a width of 50 μm and a depth of 10 μm. The spacing between adjacent micron-sized grooves is 50-53 μm. The micron-sized groove on the surface of the dental implant is a longitudinal vertical groove which is in the same direction with the central axis of the dental implant and has the same taper with the surface of the dental implant.

The nanotubes are titanium dioxide nanotubes. The aperture of the nanotube is 100 +/-15 nm, the thickness of the tube wall is 10 +/-2 nm, and the length of the tube is 2.2 +/-0.2 mu m. The caliber nanotube can adsorb more fibronectin and promote cell adhesion and extension, not only can support the proliferation of bone marrow mesenchymal stem cells and promote the expression of osteogenesis related genes, but also can promote the proliferation of gingival fibroblasts and the expression of soft tissue sealing related genes, and achieves the effect of osteogenesis and soft tissue sealing.

The manufacturing method of the invention comprises the following steps: preparing micron-sized grooves on the surface of the pure titanium dental implant, cleaning, and then preparing the titanium dioxide nanotube by performing an electrochemical anodic oxidation method on the dental implant with the micron-sized grooves.

The equipment used for preparing the micron-sized groove on the surface of the pure titanium dental implant is an inductive coupling plasma etcher, SU-8 photoresist with the thickness of 8 microns is deposited on the surface of the dental implant, and the equipment is prepared by the inductive coupling plasma etcher: the width is 50 μm, the depth is 10 μm, the distance between adjacent micron-sized grooves is 50-53 μm, after the preparation, acetone and deionized water are respectively used for ultrasonic cleaning for 10min to remove oil, 4wt% HF-5mol/L HNO₃After the solution is chemically etched for 10s, the substrate is washed by deionized water and dried for later use.

The preparation of the titanium dioxide nanotube by the electrochemical anodic oxidation method is carried out in a conventional two-electrode system electrochemical cell under the water bath condition, as shown in figure 7, the dental implant which is prepared for use after pretreatment is taken as an anode, a cathode 4 is formed by rolling a platinum sheet, the shape of the cathode is a hollow cylinder, the inner surface of the cathode has the same taper with that of the implant, the upper surface and the lower surface of the cathode are open, the cathode is sleeved outside the dental implant 1, the distance between the inner surface and the implant surface is 1cm, and the electrolyte is 0.50 wt% of NH₄F+10vol％H₂And (3) the whole anodic oxidation process is accompanied with the stirring of the magnetic stirrer 5, the electrolyte solution is controlled to keep the environmental temperature at 30 +/-2 ℃, a direct-current stabilized power supply provides an anodic oxidation power supply, then the annealing treatment is carried out for 2 hours at 450 ℃, and the deionized water is washed clean.

In the process of preparing the titanium dioxide nanotube, the anode is oxidized for 3 hours under the voltage of 30v, and the prepared nanotube has the aperture of 100 +/-15 nm, the tube wall of 10 +/-2 nm and the tube length of 2.2 +/-0.2 mu m.

Three groups of titanium dioxide nanotubes prepared under the voltage of 10v, 30v and 60v according to the present invention are referred to as inventive example 1, inventive example 2 and inventive example 3, respectively. The pipe diameters are respectively 28 +/-5 nm, 100 +/-15 nm and 203 +/-22 nm, and the pipe lengths are respectively 2.0 +/-0.2 mu m, 2.2 +/-0.2 mu m and 2.5 +/-0.3 mu m. Namely, the micron/nanometer surface with the micro-groove and the nanometer tube is prepared.

The invention has the beneficial effects that:

the control group in the experiment was untreated pure titanium:

1) using the CCK-8 assay, cell proliferation at the material surface was reflected by the absorbance of the solution at OD 450.

Proliferation results (OD450 absorbance value) of mesenchymal stem cells on material surface at different time points

Grouping	1D	3D	7D
				Pure titanium	0.183±0.051	0.831±0.136	1.372±0.201
Inventive example 1	0.176±0.034	0.843±0.034	1.357±0.218
				Inventive example 2	0.181±0.018	0.801±0.091	1.368±0.186
Inventive example 3	0.081±0.011	0.311±0.031	0.532±0.110

Proliferation results (OD450 absorbance value) of gingival fibroblast cells on the surface of the material at different time points

Grouping	1D	3D	7D
				Pure titanium	0.186±0.034	0.432±0.102	0.721±0.142
Inventive example 1	0.196±0.057	0.498±0.210	0.701±0.321
				Inventive example 2	0.314±0.033	0.769±0.121	1.012±0.211
Inventive example 3	0.098±0.012	0.243±0.030	0.454±0.101

The experimental result shows that compared with the pure titanium of a control group, the embodiment 1 of the invention can support the proliferation of the bone marrow mesenchymal stem cells and the proliferation of the gingival fibroblasts; the embodiment 2 of the invention can support the proliferation of the bone marrow mesenchymal stem cells and obviously promote the proliferation of gingival fibroblasts; the embodiment 3 of the invention obviously inhibits the proliferation of the mesenchymal stem cells and the gingival fibroblasts.

2) The qRT-PCR is adopted to detect the expression levels of osteogenesis related genes Runx2, ALP, OCN and Col-1 of the mesenchymal stem cells of the bone marrow, and the expression levels of soft tissue sealing related genes Integrin- β 1, Vincultin, Fibronectin and Col-1 of gingival fibroblasts.

Expression level of osteogenesis related gene of bone marrow mesenchymal stem cell on surfaces of two groups of experimental group samples

Grouping	Runx2	ALP	OCN	Col-1
					Inventive example 1	0.975±0.165	1.018±0.360	1.219±0.130	0.889±0.123
Inventive example 2	2.341±0.176	3.874±0.370	2.489±0.288	3.894±0.382
					Inventive example 3	3.432±0.324	5.843±0.423	4.435±0.564	6.654±0.548

Expression level of related genes of gingival fibroblast soft tissue sealing on surfaces of two groups of experimental group samples

Grouping	Integrin-β1	Vinculin	Fibronectin	Col-1
					Inventive example 1	1.021±0.132	1.217±0.154	0.894±0.201	1.074±0.284
Inventive example 2	2.321±0.484	3.717±0.321	3.215±0.331	2.642±0.531
					Inventive example 3	0.647±0.101	0.638±0.019	0.801±0.103	0.693±0.011

The result shows that pure titanium is used as a control group, and the embodiment 1 of the invention can basically support the expression of the osteogenesis related gene of the bone marrow mesenchymal stem cells and the expression of the soft tissue sealing related gene of the gingival fibroblasts; the embodiment 2 of the invention obviously promotes the expression of the osteogenesis related gene of the bone marrow mesenchymal stem cell and the expression of the gingival fibroblast soft tissue sealing related gene; although the embodiment 3 of the invention obviously promotes the expression of the osteogenesis related gene of the bone marrow mesenchymal stem cell, the invention obviously inhibits the expression of the gingival fibroblast soft tissue sealing related gene.

The results of CCK-8 and qRT-PCR were combined: the invention example 1 has no obvious difference compared with the pure titanium of the control group; the invention example 3 obviously inhibits the proliferation of the mesenchymal stem cells and the gingival fibroblasts; only the example 2 of the present invention can not only support the proliferation of the bone marrow mesenchymal stem cells and promote the expression of the related genes of osteogenesis, but also promote the proliferation of gingival fibroblasts and the expression of the related genes of soft tissue sealing, i.e. the example 2 of the present invention (the pipe diameter is 100 +/-15 nm, the pipe length is 2.0 +/-0.2 μm) achieves the effect of both osteogenesis and soft tissue sealing.

While the foregoing is directed to the preferred embodiment of the present invention, various changes and modifications may be made in the details without departing from the spirit and scope of the invention, and it will be apparent to those skilled in the art that various changes, substitutions, and alterations can be made herein without departing from the spirit and scope of the invention.