JPS60185563A - Ceramic member for prosthesis - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ceramic member used for prosthesis of missing bones and missing tooth roots in the fields of orthopedics, dentistry, etc.

In recent years, ceramic materials have come to be used as prosthetics and filling materials for defective bones and tooth roots in fields such as orthopedics and dentistry. This is because it has become clear that ceramic materials are less harmful to the human body than metals and polymeric materials, and have superior affinity with tissues. In view of this trend, alumina materials are now commonly used as materials, and recently apatite materials have been attracting attention. In addition, a composite structure in which apatite is thermally sprayed onto an alumina core material has also been devised.

However, the above materials and structures have the following problems.

As for alumina, it is true that it is inert in living organisms, so
Although there is no temporary injection, it cannot be expected to promote the effect of the ashes, and if used repeatedly over a long period of time, it may fall out from the filled part.

Apatite has excellent effects in terms of its compatibility with living organisms and growth of new bone, but it has one drawback: it is weak in strength.

In addition, composite structures with apatite sprayed on the surface have a large thermal expansion coefficient between alumina and apatite.
There is a problem in that it may peel off when heated.

The present invention has been made in view of one or more of the deficiencies of the prior art.

It is an object of the present invention to provide a ceramic member for living bone prosthesis which 1. has excellent strength; 2. does not require any temporary injection; and 3. has excellent ability to integrate with new bone.

In developing M binding materials, the following three characteristics must be taken into consideration: 1) strength, 2) stability, and 3) integral fusion properties, and the present invention combines these three characteristics into one material. This problem was solved by creating a so-called composite structuring.

This problem was solved by a composite combination of non-toxic, high-strength ceramics and materials that attract new bone, have excellent proliferative properties, and are ultimately absorbed by tissues. The place is.

1) The core is made of dense ceramics and the outer layer is made of porous ceramics.

2) The above-mentioned bioprosthetic ceramic member, characterized in that the outer layer portions are integrally bonded to each other, and a biocompatible and bioabsorbable material is retained in the pores of the porous ceramic. Claim 1, characterized in that the compatible, bioabsorbable material is a calcium phosphate compound.
This is the prosthetic ceramic member described in 2.

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a diagram schematically explaining the structure of the member of the present invention.

(1) is the ceramic part that forms the core, (2) is the core (1
) is a porous layer provided integrally on the outside. (1)
and (2) may not necessarily be made of the same material, but in any case they must be integrally bonded. The materials for (1) and (2) are zirconia (P, S,
) and high-strength alumina are preferred.

(3) is a layer impregnated with the porous layer (2) and retained in the pores. 1) He has a strong tendency towards ``IA'' elbows.

(3) The impregnated retention layer does not necessarily require heat treatment after impregnating the porous layer (2) in the form of a slurry, but depending on the type of material to be impregnated, heat treatment is recommended for osteogenesis of new bone. It may be effective for promotion. For example, in the case of hydroxyapatite, its osteogenic properties are improved when it is heat-treated at several hundred degrees. In this case, because the coefficients of thermal expansion of abatite and the ceramics (1) or (2) are different, even if they are temporarily sintered and bonded to each other by heat treatment, they will peel off during cooling, and the impregnated layer will essentially disappear. (1') and (2) may be in a state where they are not bonded at all, but in the present invention, it is not an essential condition that they are bonded to each other; If it is, the original purpose will be achieved. On the contrary, the present invention is based on the premise that it is essentially difficult to bond the impurity layer and the ceramic layer by diffusion bonding through heat treatment. It also has a lockable structure.

When a member having the above-mentioned structure is prosthesized to a living body, new bone is attracted, introduced, proliferated, and infiltrates into the retaining layer because it has osteoinductive properties. The impregnated retention layer is gradually replaced by new bone, and eventually the porous layer becomes filled with new bone.

For this reason, even if the materials (1) and (2) and the new bone do not have the property of integral fusion, the two will be firmly connected due to a kind of anchor effect that has countless roots. Even if subjected to long-term repeated stress, it will no longer fall off.

On the other hand, since the materials (1) and (2) are made of a high-strength ceramic material such as zirconia, there is no problem in terms of strength or damage.

Here, an example of application of the present invention to an actual living body will be described.

, Zirconia ceramics (P) is used as a ceramic material.
．． S. Z. ), the center is dense and the surface is porous (60% porosity), and the composite structure is integrally fired.Then, the pores are impregnated with calcium phosphate slurry and heat treated at 900 degrees. did.

Next, this composite ceramic was filled into an artificially created bone defect in a dog, and its compatibility with the living body was tested.

As a result, after a few weeks, the effect of attracting new bone to the impregnated layer was already observed, and after 8 months, most of the new bone was filled with new bone, and the new bone appeared to have taken root in the porous layer of zirconia. It was confirmed that .

As detailed above, the present invention has excellent biocompatibility, new bone attraction, and osteogenicity in terms of strength, and can be firmly integrated without falling off even after repeated use over a long period of time. This will bring great news to orthopedics and dentistry.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram of the member of the present invention. ■・・・・・・Core ceramic part ■・・・Porous layer ■・・・・・・Impregnated layer Patent applicant: Koransha Co., Ltd. Representative Tadashi Fukagawa Figure 1 2 @) 1 summer

Claims (1)

[Claims] 1) A structure in which the core is made of dense ceramics and the outer layer is made of porous ceramics, and the core and the outer layer are integrally bonded to each other, and the pores of the porous ceramics are 1. A prosthetic ceramic member characterized by retaining a biocompatible and bioabsorbable material. 2) Claim 1, wherein the biocompatible and bioabsorbable material is a calcium phosphate compound.
The prosthetic ceramic member described in .