JPS6335247A - Implant for artificial dental root - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a novel artificial tooth root implant. More specifically, the present invention relates to an implant for an artificial tooth root that has excellent biocompatibility and mechanical strength as well as good tactility.

Conventional technology In recent years, with the remarkable development of medical technology, artificial materials such as artificial organs, artificial blood vessels, artificial joints, artificial bones, and artificial tooth roots are inserted into living organisms to replace lost parts and functions of living organisms. So-called implantology, which helps people recover, is in the spotlight.

Particularly in dental treatment, when an artificial tooth is inserted into the area where a tooth root has been removed, an artificial tooth root is actively used to fix the artificial tooth to the bone.

Conventionally, known materials for artificial tooth roots include metal materials such as titanium, tantalum, cobalt-chromium alloys, and stainless steel, as well as single crystal, polycrystal, and porous alumina materials.

However, since the former metal material has poor affinity with living tissue, if it is used for a long period of time, it will inevitably fall off, and the eluted ions may harm the living body. On the other hand, the alumina material undergoes almost no chemical changes in living organisms, is stable over a long period of time, is harmless to living organisms, and has relatively good biocompatibility, but does not form chemical bonds with living tissues. Therefore, it cannot be said to be a fully satisfactory material.

Therefore, recently, tricalcium phosphate and hydroxyapatite have attracted attention as materials that have a composition similar to that of bones and teeth and have excellent biocompatibility ff1W, and it is possible to prepare artificial tooth roots using these materials. It has been proposed (for example, Japanese Patent Application Laid-open No. 5
(See Publication No. 6-5481).

These materials are harmless to living organisms, have excellent biocompatibility, and have the characteristics of strongly bonding to natural bone.

In addition, glass with good affinity for bone tissue, so-called bioglass, has attracted attention as a biomaterial, and for example, a bonding agent for bone or dental surgery made of this glass and a methacrylate-based synthetic resin has been proposed (Japanese Patent Application Laid-Open No. 51-1991). -98754). This bioglass is made of 5i02-Na20-based glass or Sio2-Na20-20-MgO-based glass containing a large amount of CaO and P2O5, and is harmless to living organisms and has biocompatibility. It not only has good properties, but also has the property of strongly bonding with natural bone. This is because hydroxyapatite is formed on the glass surface in vivo.

As mentioned above, these apatite materials and bioglass materials have the excellent characteristics of being harmless to living organisms, having excellent affinity, and bonding strongly with natural bone.
The strength is inferior to metal materials such as titanium or ceramic materials such as alumina, and artificial tooth roots formed from these materials have the disadvantage that they may break if strong impact or pressure is applied.

As a solution to overcome these drawbacks, for example, a sprayed layer of hydroxyapatite powder, a sprayed layer of a mixed powder of ceramic powder and hydroxyapatite powder, or a sprayed layer of ceramic powder on the outer periphery of a ceramic implant core material, Next, an implant having thermal spraying of hydroxyapatite powder has been proposed (Japanese Patent Publication No. 46911/1983).

Problems to be Solved by the Invention Incidentally, although these implants have excellent biocompatibility and mechanical strength, the thermal sprayed layer (hydroxyl abatement) lacks acid resistance, so when used as an artificial tooth root, they have poor resistance. The caries resistance is not necessarily satisfactory.

The object of the present invention is to solve these problems and provide an implant for an artificial tooth root that has excellent biocompatibility and mechanical strength, as well as good tactility.

Means for Solving the Problems The present inventors have conducted extensive research to develop implants for artificial tooth roots that have excellent biocompatibility, mechanical strength, and tactility, and have found that they are biocompatible. Among excellent apatites, halogen apatite has particularly excellent acid resistance, while hydroxyapatite has particularly excellent biocompatibility. Alternatively, the inventors have discovered that the objective can be achieved by providing a thermally sprayed layer of halogenapatite powder partially converted to hydroxyapatite, and based on this knowledge, the present invention has been completed.

That is, the present invention provides an implant for an artificial tooth root, characterized in that a sprayed layer of halogen apatite powder is provided on the surface of a metal or ceramic implant core material, and a metal or ceramic implant core material on the surface of the implant core material. The present invention provides an artificial tooth root implant, characterized in that it is provided with a sprayed layer of halogenapatite powder partially converted to hydroxyapatite.

In the implant of the present invention, a metal material or a ceramic material is used as the core material, and examples of the metal material include metals such as titanium and tantalum, and alloys such as cobalt-chromium alloys and stainless steel. Examples of ceramic materials include Az2o3, ZrO2, Tl
O2,0aO-At203, At205 51o2 glass, Sj, 02-Na2OC! Examples include ao-P205 glass (bioglass) and carbon.

In addition, the halogen apatite used in the present invention may be synthetic hydroxyapatite obtained by various methods or hydroxyapatite [Ca1o(PO4)6(OH )2] By replacing the iyne hydroxyl with halogen ions such as chloride ions and fluoride ions, or carbonate-containing apatite CC! a1o (PO+)600x] can be easily obtained by replacing the carbonate ion with the above...rogen ion, and has a structure represented by the formula %) (where X is a...rogen atom such as chlorine or fluorine). It has excellent acid resistance.

In the present invention, this apatite powder is thermally sprayed onto the surface of a metal or ceramic implant core material to form a thermally sprayed layer. The particle size of the powder is 0.05
A range of 0.5 μm to 0.5 μm is preferred, and the thermal spraying is carried out using a conventional thermal spraying device, preferably a plasma spraying device. At this time, if unevenness on the surface of the core material is required,
The surface may be roughened by machining such as cutting or grid blasting. Furthermore, if desired, after a thermally sprayed layer of a commonly used bonding agent is provided on the surface of the core material, a thermally sprayed layer of halogen apatite powder may be provided thereon.

The thickness of the sprayed layer of halogenapatite powder in the implant of the invention is at least 0.05111+, preferably in the range from 0.1 to 1n.

In the present invention, in order to improve the biocompatibility of the part that comes into contact with living tissue, the halogen ions of the halogen apatite in the thermally sprayed layer in this part are replaced with hydroxide ions. Preferably, the apatite '6-hydroxyapatite is converted. Hydroxyapatite has a composition similar to that of bones and teeth and has excellent biocompatibility, and the hydroxyapatite coating layer formed as described above is porous, so bone cells can enter the pores. This will ensure a strong fixation. The replacement of the halogen ions of the halogen apatite with hydroxyl ions is carried out by heating the radiation layer of the halogen apatite powder in the portion that comes into contact with living tissue in a steam atmosphere, preferably at a temperature in the range of 1000 to 1200°C. .

Next, the artificial tooth root implant of the present invention will be explained with reference to the accompanying drawings. FIGS. 1, 2, and 3 are sectional views showing different examples of the structure of the artificial tooth root implant of the present invention, respectively. FIG. 1 shows a structure in which only a halogen apatite layer 3 is provided on the surface of a core material in which a pedestal portion 1 and a protrusion 2 are integrally formed of a metal material or a ceramic material, and FIG. 2 shows a structure in which only a halogen apatite layer 3 is provided. FIG. 3 shows a structure in which a mixed layer 4 of hydroxyapatite is provided, and FIG. 3 shows a structure in which a hydroxyapatite layer 5 is provided on the bottom surface of the core material, and a halogen apatite layer 3 is provided on the top surface. .

Effects of the Invention The artificial tooth root implant of the present invention not only has excellent biocompatibility and mechanical strength, but also has good tactility.
It has excellent characteristics.

Example Next, the present invention will be explained in more detail with reference to Examples.

Example 1 Plasma spraying equipment (Meteco Type-3M type,
Fluorine apacite powder was thermally sprayed onto the surface of a titanium implant core material as shown in FIG. 1 using a 3MB' thermal spraying gun (6MR-630 model with power supply). The conditions for thermal spraying are as follows.

Argon gas 100psi, hydrogen gas 50pni,
The flow rate of argon/hydrogen is 80 scale/1 with 3M type thermal spray equipment.
5 scales. Arc voltage 70v, arc 1jtf5o
Under oA conditions, an argon-hydrogen plasma jet flame with a length of about 10 m is generated, the implant core material is placed at the tip of the frame, and fluoroapacite powder is fed from the feeder into the frame, and the coating film is formed while changing the position of the core material. Plasma spraying was performed to ensure uniform adhesion.

A fluoroapatite layer having an average thickness of 200 μm was coated by thermal spraying for 10 minutes, and an artificial tooth root implant as shown in FIG. 1 was obtained.

Example 2 In exactly the same manner as in Example 1, a thermally sprayed layer of fluorocarbon apatite powder with an average thickness of 200 μm was provided on the surface of a titanium core material, and only the upper part was coated with platinum foil (F-
(in order to prevent ion exchange between We created an implantra for artificial tooth roots.

[Brief explanation of the drawing]

1, 2, and 3 are cross sections and diagrams showing different examples of the structure of the implant for artificial tooth roots of the present invention, respectively. FIG. 1 shows only the halogen apatite layer, and FIG. 2 shows the halogen apatite layer only. Figure 3 shows a case where the bottom part is a hydroxyapatite layer and the top part is a halogenapatite layer. In the figure, numeral 1 is a pedestal portion, 2 is a protrusion, 3 is a halogenapatite layer, 4 is a mixed layer of halogenapatite and hydroxyapatite, and 5 is a hydroxyapatite layer. Figure 1 Figure 2

Claims (1)

[Scope of Claims] 1. An implant for an artificial tooth root, characterized in that a sprayed layer of halogen apatite powder is provided on the surface of a metal or ceramic implant core material. 2. An artificial tooth root implant characterized in that a sprayed layer of halogen apatite powder partially converted to hydroxyapatite is provided on the surface of a metal or ceramic implant core material.