JPS63132810A - Artificial dental root - Google Patents

Abstract

PURPOSE:To obtain an artificial dental root surely and stably fixable to bone over a long period and giving effectively reinforced base, by mixing fibrous apatite and exposing a part of the fibrous apatite on the surface. CONSTITUTION:The objective artificial dental root contains mixed fibrous apatite (especially preferably hydroxyapatite whisker, fluoroapatite whisker, woolly apatite carbonate, etc.) in a manner to expose a part of said fibrous apatite on the surface of the root. Since the remaining part of the fibrous apatite exposing a part thereof on the surface is deeply embedded in the base, it is resistant to falling off from the base during use and resistant to absorption and dissolution. The artificial dental root is preferably made of one or more kinds of base materials selected from polymer resins and metals (preferably formed of a polymer resin and containing embedded metallic core material).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an artificial tooth root used in dental treatment, and more specifically, to an artificial tooth root mixed with fibrous apatite and having various excellent properties.

Previously, an artificial tooth root mixed with apatite was made of a composition in which granular or powdered synthetic hydroxyapatite, its calcined product, or a mixture thereof was dispersed in an organic matrix, and the interfacial phase that came into contact with the bone was created. An artificial tooth root composed of both a hydroxyapatite phase and an organic layer has been proposed (Japanese Unexamined Patent Publication No. 55-50349).

It is said that by providing a hydroxyapatite phase that can adhere to bone in a part of the interfacial phase, it has an appropriate adhesion force to bone.

However, since the artificial tooth root described in JP-A-55-50349 mentioned above uses granular or powdered hydroxyapatite, the hydroxyapatite in the interfacial phase is affected by vibrations during use. In addition to being easily detached from the organic layer due to such factors, it is also easy to disappear due to absorption and elution, and for this reason, the affinity between the tooth root and bone decreases during the use of artificial tooth roots, and the tooth root is stably retained in the jawbone for a long period of time. There was a problem that it was not done.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide an apatite-mixed artificial tooth root that can be stably fixed to bone for a long period of time.

Means and Effects for Solving the Problems In order to achieve the above object, the present invention provides an artificial material characterized in that fibrous apatite is mixed and a part of the fibrous apatite is exposed on the surface of the mixture. Provides the root of the tooth.

In the artificial tooth root of the present invention, the remaining part of the fibrous apatite that is partially exposed on the surface is buried deep inside the base, so it will not detach from the base during use and will not disappear due to absorption or elution. do not have. Therefore, in the artificial tooth root of the present invention, the apatite that exists at the contact point with the bone and functions to fix the artificial tooth root and the jawbone does not easily fall off or disappear from the artificial tooth root. When installed in the jawbone, this tooth root is held stably for a long period of time. Moreover, since the apatite mixed in the base is fibrous, it has a higher reinforcing effect on the base compared to granular or powdered apatite, and the artificial tooth root of the present invention has the advantage of high strength.

The present invention will be explained in more detail below.

The artificial tooth root of the present invention is formed by mixing fibrous apatite as described above so that a portion of the fibrous apatite is exposed on the surface.

Here, the type of fibrous apatite is not particularly limited, but for example,
6, whisker-like hydroxyapatite, whisker-like fluoroapatite, whisker-like carbonate apatite, flocculent hydroxyapatite, flocculent fluoroapatite, flocculent, described in JP-A No. 61-106167, No. 61-201018, No. 61-201019, etc. Carbonate apatite and the like can be suitably used, and one type or a mixture of two or more of these can be used. In this case, although there are no limitations on the properties of these whisker-like or flocculent apatites, it is particularly preferable to use those whose short fibers constituting them have an average fiber strength X5 to 20p and an average fiber length of 100p to 5ffI11.

The artificial tooth root base material used in the present invention includes polymer resins, metals, glass, ceramics, and the like.

In particular, polymer resin or metal is desirable.

There is no limit to the type of polymer resin, but the tensile strength is 150
It is preferable to use a material with a molecular weight of more than kg/cd, such as polyethylene or hard vinyl chloride resin.

Teflon resin, polyamide resin, Kevlar resin.

Polymethyl methacrylate, bisphenol A-glycidyl methacrylate condensate, polysulfone resin, polyester resin, polycarbonate.

Poly-2-hydroxyethyl methacrylate and the like can be suitably used.

If the base material is metal, the type of metal is not limited, but stainless steel and cobalt-chromium alloys are less corrosive and cause fewer problems to the human body.

It is preferable to use titanium, titanium alloy, or the like.

In the artificial tooth root of the present invention, the mixing ratio of fibrous apatite to the base material can be varied depending on the material of the base material used. When the base material is a polymer resin, the mixing ratio of fibrous apatite ( weight ratio) is 1 to 90%, especially 10
~50%, and when the base material is metal, the mixing ratio (weight ratio) of fibrous apatite is preferably 1 to 30%, particularly 5 to 20%, thereby obtaining good affinity for bone. be able to.

Further, when the artificial tooth root of the present invention is formed of a polymer resin mixed with fibrous apatite, a metal rod can be embedded as a core material in the center of the tooth root to reinforce the tooth root.

Here, as the metal rod, it is possible to use a metal that corrodes easily, such as iron, since it is covered with a polymer resin.
Stainless steel, cobalt-chromium alloys, and titanium alloys are less corrosive and pose fewer problems to the human body, in case cracks occur in the polymer resin.

It is preferable to use platinum, gold alloy, silver, nickel, tantalum alloy, etc.

There are no particular restrictions on the method of manufacturing the artificial tooth root of the present invention. For example, a method of mixing apatite with a polymer resin is to heat the polymer resin to a temperature higher than its melting point, melt it, add fibrous apatite to it, and then use a kneader or A method in which the polymer resin is kneaded with an exfluder and then cooled. A method in which the polymer resin is dissolved in a solvent, fibrous apatite is added and mixed, and then the solvent is distilled off. A method in which fibrous apatite is added to the monomer and mixed, and then polymerized. method etc. may be adopted.

The method of mixing apatite with metal is to thoroughly mix metal powder and fibrous apatite, press-form it or use a binder to form a compact, and sinter it in an inert atmosphere or vacuum atmosphere. It is possible.

In addition, methods for molding a base material mixed with fibrous apatite include, for example, when the base material is a polymer resin, a method in which the mixed base material is previously molded into the shape of an artificial tooth root, and the surface thereof is polished; Methods include extrusion molding into a long round bar, cutting it into appropriate lengths, and polishing the corners, and forming into a block and cutting this block into the shape of a tooth root. It is possible. Furthermore, when manufacturing a tooth root with a metal core material embedded inside, a method may be adopted in which the fibrous apatite mixed base material is formed into a lump with the core material embedded inside, and the lump is cut.

In addition, when manufacturing the artificial tooth root of the present invention, it is preferable to perform cutting or polishing as described above, whereby a portion of the fibrous apatite can be reliably exposed on the tooth root surface.

Further, the artificial tooth root of the present invention can have a crown attached to its upper part during use.

EXAMPLES Next, the present invention will be specifically explained with reference to examples, but the present invention is not limited to the following examples.

11-pen nylon 6 (Amilan CM1017 manufactured by Toshishiku Co., Ltd.) and fibrous hydroxyapatite (cotton-like apatite) with a thickness of 5 to 15 μm were kneaded at a weight ratio of 1:1 using an extrusion molding machine. , formed into a round bar shape of 5 mmφ. This length is 1
By cutting it into 5 m pieces and polishing the corners, the fibrous apatite 2 was mixed with the polymer resin 1 as shown in Fig. 1.
In addition, an artificial tooth root 3 with a part of the apatite 2 exposed on the surface was obtained.

Large spot Nylon 6 (same as above) was heated to 270"C and melted.

In addition to this, fibrous hydroxyapatite with a thickness of 5 to 15 μm (
Add flocculent apatite at a weight ratio of 1:1 and knead well. A stainless steel round rod with a thickness of 2 m and a length of 12 m was embedded in this and allowed to cool to room temperature and solidify.

Next, the resin was cut into a round rod shape with a thickness of 5 m and a length of 151I11, using the embedded stainless steel round rod as the core material. An artificial tooth root 3 was obtained in which the mixture was mixed, a part of the apatite 2 was exposed on the surface, and a core material 4 made of stainless steel was embedded in the center.

Example 3 Bisphenol A-glycidyl methacrylate and thickness 5
~15μ of fibrous hydroxyapatite (cotton-like apatite) was mixed well at a weight ratio of 2:3, 0.01% of benzoyl peroxide was added thereto, and the mixture was heated at 100℃ for 4 hours.
Allow time to polymerize. The obtained polymer resin was cut into a round rod shape with a thickness of 5 m and a length of 15 mm to obtain an artificial tooth root as shown in FIG.

1) Hair titanium powder and fibrous hydroxyapatite (cotton-like apatite) with a thickness of 5 to 15 μm are thoroughly mixed at a weight ratio of 9:1, and press-molded at a pressure of 1 ton/a#.

This compact is sintered at 1200° C. in an argon gas stream. The sintered body was cut into a round bar shape with a thickness of 5 m and a length of 15 m.
As shown in FIG. 3, an artificial tooth root 3 was obtained in which fibrous apatite 2 was mixed with metal 5 and a portion of apatite 2 was exposed on the surface.

The artificial tooth roots of Examples 1 to 4 were all stably fixed in the jawbone over a long period of time. In contrast, all of the artificial tooth roots manufactured in the same manner as Examples 1 to 4 except that powdered hydroxyapatite was used instead of fibrous hydroxyapatite lost adhesive strength between the tooth root and bone after long-term use. It deteriorated and was no longer stably retained within the jawbone.

As described in detail, the artificial tooth root of the present invention has the remainder of the fibrous apatite exposed on the surface embedded inside the tooth bone, so that the apatite can be detached and detached due to vibration after being fixed to the jawbone. This prevents as much as possible the loosening of the attachment between the tooth root and the bone due to the elution of the tooth, and allows it to be stably retained in the jawbone for a long period of time.

In addition, in the artificial tooth root of the present invention, the fibrous apatite acts as a filler, and the base is more effectively reinforced than when powdery apatite is mixed. Further, when the base body is made of a polymer resin, the impact when biting something with the teeth is absorbed by the tooth roots, so there is an advantage that the burden on the jawbone can be reduced.

[Brief explanation of the drawing]

, FIG. 1, FIG. 2, and FIG. 3 are sectional views each showing an embodiment of the present invention. 1... Polymer resin, 2... Fibrous apatite, 3...
...Artificial tooth root, 4...Metal core, 5...Metal. Figure 1 Figure 2' Figure 3

Claims (1)

[Scope of Claims] 1. An artificial tooth root characterized by mixing fibrous apatite and exposing a portion of the fibrous apatite on its surface. 2. The artificial tooth root according to claim 1, which is formed of one or more base materials selected from polymer resins and metals. 3. The artificial tooth root according to claim 1, which is formed of a polymer resin and has a metal core material embedded inside.