JP2004224658A - Method of joining member for living body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a large sized compound body, an optionally shaped compound body or a compound body having different porosity which is formed by sticking calcium phosphate-based members each composed of a previously fired and molded dense body or porous body. <P>SOLUTION: In the method of joining members for living body performed by joining a plurality of members for living body, a plurality of the calcium phosphate-based porous bodies are joined and fired by applying a gelated binder in which powder of the same material as the member to be joined is added on 20-80% of a joining surface of the calcium phosphate-based porous body. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for joining biological members such as artificial bones.
[0002]
[Prior art]
Bone prostheses, which are used in dental, neurosurgery, plastic surgery, orthopedic surgery, etc. to replace artificial teeth, artificial bones, etc., are strong, have no harm to living organisms, and have high compatibility with living tissues. Because of its easy integration with bone, a calcium phosphate compound, especially a dense or porous body of hydroxyapatite, which is a main component of living bone, is widely used clinically. For an artificial joint or the like used to support a load, a dense body having a porosity of 0 to 15% and a porous body having a porosity of about 55 to 85% are generally used.
[0003]
Currently, bone augmentation materials such as hydroxyapatite are used as products such as hydroxyapatite molded products, which are machined into a predetermined shape by machining, granules obtained by pulverizing molded products, powder paste, etc. This hydroxyapatite molded product is usually molded using a calcium phosphate-based compound by a method such as a slip casting method or a pressing method to form a molded body of a dense body or a porous body, and drying and firing as necessary. Manufacturing.
[0004]
However, in the production of hydroxyapatite by such a production method, cracks considered to be caused by shrinkage during drying or baking of a molded article are apt to occur, and the yield is very poor. Was very difficult to produce. For this reason, when a large product is required, a small formed body has been used by connecting it with a metal wire or the like. Also, it was extremely difficult to produce a specially shaped product. Furthermore, there were cases where a single hydroxyapatite molded product required a dense part where the necessary parts were used and a porous part where the other parts were used.However, it is extremely difficult to manufacture such products in one piece. Difficult.
[0005]
However, recently, the use of the hydroxyapatite molded product has been expanding, and a hydroxyapatite molded product having a large shape or a complicated shape has been desired. In response to such demands, there has been proposed a method of joining molded bodies with an adhesive or an intermediate layer interposed therebetween, but it is difficult to obtain sufficient joining strength and maintain the joining strength for a long period of time. Met.
[0006]
As a related art, as a method of joining hydroxyapatite molded bodies having different porosity, a slurry in which primary particles of bonding ceramics of the same raw material as the molded body are dispersed is interposed on a joint surface of the molded body. It has been proposed to conclude (see Patent Document 1).
[0007]
[Patent Document 1]
JP-A-2000-169251 (claims, claim 8).
[0008]
However, in this prior art, the joining strength of a molded article is improved because the slurry in which the primary particles of the ceramic for joining are dispersed is buried in pores existing over the entire joining surface of the article to be joined. Although the strength is excellent, the pores originally formed in the porous body member for living body are lost in this portion, and blood and cells, which are particularly important in the body member, can enter the pores. This was largely impeded at the joint.
[0009]
[Problems to be solved by the invention]
The present invention seeks to obtain a composite having a large shape, a composite having an arbitrary shape, and a composite having a different porosity by bonding together a calcium phosphate-based member made of a dense body or a porous body which has been calcined in advance. Is what you do.
[0010]
[Means for solving the problem]
The present invention relates to a joining method for a living body member, comprising joining a plurality of living body members, wherein powder of the same material as the member to be joined is added to 20 to 80% of the joining surface of the calcium phosphate-based porous body. A method of bonding a biomedical member, wherein a plurality of calcium phosphate-based porous bodies are bonded and sintered by applying the gelled binder, wherein one of the members to be bonded is a porous member, The method according to claim 1, wherein the method is a porous member or a dense body having the same or different porosity as the porous member, wherein the gel binder is a water-soluble epoxy resin compound. 3. The method for joining biological members according to claim 1 or claim 2, wherein the slurry is a mixture of a hardener and a powder of the same material as the member to be joined (claim 3), wherein the gel binder is gelatin, agarose or The method for bonding a biomedical member according to claim 1 or 2, wherein the mixture is a mixture of a powder of the same material as the member to be bonded and the gel binder. The method according to claim 1 or 2, wherein the mixture is a mixture with a powder of the same material.
[0011]
That is, the present invention is to join a calcium phosphate-based porous body having the same or different porosity, or to join a calcium phosphate-based porous body and its dense body to obtain a composite thereof, For this purpose, a gel-like binder obtained by adding powder of the same material as the member to be joined is applied to 20 to 80% of the joining surface of the molded body, and the molded body is sintered and joined.
[0012]
[Action]
According to the present invention, it is possible to produce a large-sized calcium phosphate-based molded body, which was conventionally extremely difficult to manufacture, and to use a large-sized molded product using a small-sized calcium phosphate-based molded body having a good product yield. You can do it. Further, according to the present invention, a plurality of porous biological members can be joined so that blood and cells can penetrate even at the joining surface of the porous body. Further, it is possible to form a calcium phosphate composite in which a porous body and a dense body are joined.
[0013]
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is a method of bonding a calcium phosphate-based compound that has been calcined in advance by bonding. The calcium phosphate compounds used in the present invention include CaHPO ₄ , Ca ₃ (PO ₄ ) ₂ , Ca ₅ (PO ₄ ) ₃ OH, Ca ₄ O (PO ₄ ) ₂ , Ca ₁₀ (PO ₄ ) ₆ (OH) ₂ , Main components are CaP ₄ O ₁₁ , Ca (PO ₃ ) ₂ , Ca ₂ P ₂ O ₇ , Ca (H ₂ PO ₄ ) ₂ , CaP ₂ O ₇ , Ca (H ₂ PO ₄ ) ₂ · H ₂ O, etc. Or a porous body of a calcium phosphate compound.
[0014]
The sintered body of the calcium phosphate compound to be joined is manufactured by a known method. A dense sintered body of a calcium phosphate-based compound is produced by press-molding a raw material fine powder of calcium phosphate with a press and sintering it at a predetermined temperature. Since a dense sintered body of a calcium phosphate-based compound is relatively easy to produce, it is easy to produce a large product, but also in this case, it is difficult to produce a complex shape.
[0015]
On the other hand, a porous sintered body of a calcium phosphate compound is prepared by adding water and a foaming agent to a raw material powder of calcium phosphate, stirring and foaming, and then drying and sintering this at a predetermined temperature. Can be obtained by There are various types of foaming agents used here. For example, a surfactant such as triethanolamine laurate is used.
[0016]
The bonding of the calcium phosphate compound in the present invention is not only bonding between porous bodies having the same porosity, but also bonding between a plurality of porous bodies having different porosity and bonding between the porous body and the dense body. You may. FIG. 1 is a perspective view of a composite body 15 in which six porous bodies 10, 10,... Having the same porosity and the same size are joined. FIG. 2 is a perspective view of a composite 25 in which porous bodies 20 and dense bodies 21 are alternately laminated and joined. FIG. 3 is a perspective view of a composite 35 in which the periphery of the dense body 30 is surrounded and joined by the porous body 31.
[0017]
In joining these calcium phosphate compounds, a gel binder obtained by adding a powder of the same material as the calcium phosphate compound to be joined to a gel material is applied to the joint surface of the living body member, and both are adhered to each other. The two are joined by tying. The gel-like binder used here includes gelling agents such as gelatin and agarose that gel upon cooling, gelling agents for heat-coagulable proteins such as ovalbumin, and hardening agents for epoxy resin slurries. For example, a gelling agent to which is added. As the curing agent used here, an amine compound, an alcohol compound, butyric acid, cresol, phthalic acid and the like are used. In addition, a gel-like substance obtained by crosslinking and polymerizing a polymer having a hydroxyl group such as polyvinyl alcohol and a polyfunctional aldehyde such as glutaraldehyde can also be used. It is preferable that the amount of the powder of the same member as the joining member mixed in the water or alcohol solution containing the gelling agent is in the range of 50 to 70% by weight, and the gel binder has a high viscosity. If the powder of the joining member in the binder is less than 50% by weight, the fluidity of the binder increases, and the binder penetrates into the pores of the joining surface of the joining member and closes the pores of the porous body, and blood in this portion is blocked. Or the introduction of cells. On the other hand, if the powder of the joining member exceeds 70% by weight, the viscosity of the binder is insufficient and the joining is not sufficiently performed.
[0018]
In order to apply the gel-like binder to the joining surface of the joining member, any method such as brushing or dripping may be used. In the body member, it is important that the pores communicate three-dimensionally and the body fluid is well circulated throughout the body member, and it is important that blood and cells quickly enter the deep part of the body member. The application area of the gel binder is preferably set to 20 to 80% of the bonding area of the bonding member so as not to hinder. If the application area of the gel-like binder is less than 20% of the bonding area, the bonding strength is insufficient, and if it exceeds 80%, the circulation of body fluid in the bonded biological member is inhibited, and blood or cells are deeply formed in the biological member. There is a risk of not invading immediately. The bonded body of the calcium phosphate compound thus bonded is then dried, and the drying temperature is 30 to 120 ° C.
[0019]
The dried body of the calcium phosphate compound sintered body thus joined is sintered thereafter to firmly bond them. The sintering temperature here is 1000 to 1250 ° C. If the sintering temperature is lower than 1000 ° C., the sintering is insufficient and the bonding strength is insufficient. When the sintering temperature is 1250 ° C. or higher, a part of the calcium phosphate compound is thermally decomposed and a good sintered body cannot be obtained.
[0020]
The joining material member of the living body member obtained in this way has a strong joint despite the fact that the joining surface is partially joined, so that problems such as a decrease in strength at the joining surface and delamination are caused. Nothing will happen. In addition, since the area of the joining portion of the joining surface is small, pores communicate three-dimensionally in portions other than the joining portion, body fluid is smoothly circulated throughout the biological member, and blood and cells are joined. This makes it possible to quickly penetrate into a deep part over a plurality of living body members.
[0021]
【Example】
As a porous body, a porous sintered body of Ca ₁₀ (PO ₄ ) ₆ (OH) _{2 having} a porosity of 75% was used. This was divided into four porous bodies having a size of 60 mm × 60 mm × 10 mm. The adhesive was 5 parts by weight of an epoxy resin, 10 parts by weight of an amine compound, and 50 parts by weight of water based on 100 parts by weight of Ca ₁₀ (PO ₄ ) ₆ (OH) ₂ powder adjusted to a particle size of 125 μm or less. The gel binder added and mixed was used. This gel-like binder was applied in a grid pattern on the bonding surface (shape of the bonding surface; 60 mm × 60 mm) of the porous body to be bonded, and the porous bodies were bonded together. The ratio of the application area of the gel binder on the joint surface was set to 40%. Next, it was dried at 60 ° C. for 12 hours, and then sintered at 1200 ° C. for 1 hour. When the bending strength of the bonded part of this bonded body was measured by using a Shimadzu Autograph A6-10KNI with a bending strength, it was broken at a location different from the bonded part, and the bending strength was 4.0 MPa. Of the porous body (4.1 MPa).
[0022]
In addition, when the joint surface of this joined body was placed horizontally, and a blue water drop was dropped on this with a spoid, this water droplet quickly straddled the joint and reached the lower porous body. Admitted.
[0023]
【The invention's effect】
As described above, according to the present invention, a biomedical member is manufactured as a small member and joined to form a large biomedical member. Can be provided by one member. In addition, a living body member having a complicated shape can be easily created by joining those created by dividing them. Further, according to the present invention, if a porous body and a dense body are separately manufactured and then joined, a biomedical member that can be used for a part requiring strength can be simplified. Now you can make it.
[Brief description of the drawings]
FIG. 1 is a perspective view of a composite of a porous body having the same pores.
FIG. 2 is a perspective view of a laminated composite of a dense body and a porous body.
FIG. 3 is a perspective view of a composite of a dense body and a porous body.

Claims (5)

What is claimed is: 1. A method for joining biological members, comprising joining a plurality of biological members, wherein a gel-like binder is formed by adding powder of the same material as the member to be joined to 20 to 80% of the joint surface of the calcium phosphate-based porous body. A method of joining biological members, comprising applying a plurality of particles and bonding and sintering a plurality of calcium phosphate-based porous bodies. The method for joining biological members according to claim 1, wherein one of the members to be joined is a porous member, and the other is a porous member having the same or different porosity as the porous member or a dense body. The method for joining biological members according to claim 1 or 2, wherein the gel binder is a mixture of a slurry of a water-soluble epoxy resin compound and a powder of the same material as the hardener and the member to be joined. The method according to claim 1 or 2, wherein the gel binder is a mixture of gelatin, agarose, or a mixture thereof and a powder of the same material as the member to be joined. 3. The method for joining biological members according to claim 1, wherein the gel binder is a mixture of the heat-coagulable protein and a powder of the same material as the member to be joined.

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