JP2852305B2 - Artificial prosthesis materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a material for repairing a defective portion of a tooth or a bone. More specifically, the present invention uses a material having an effect of promoting osteogenesis in a living body when implanting and repairing a defective portion of a tooth or a bone, so that an implant capable of early and firmly bonding to a living tissue can be provided. It is about materials. 2. Description of the Related Art Various restorations and prostheses for defective teeth and bones with artificial materials have been conventionally performed. In other words, artificial prosthetic materials that have been conventionally applied to living bodies include metal materials, organic materials, inorganic materials, and the like, but have improvements in strength, safety, affinity with living bodies, adhesion, and the like. At present, the development of materials that are more similar to living organisms is still ongoing. In particular, when using artificial materials to repair teeth and bone defects, there is a problem with the adhesion between the living body and the material. A biological tissue forms a stable state. Bioactive materials such as hydroxyapatite and calcium triphosphate are known to improve such adhesiveness. In these bioactive materials, it is said that apatite produced by osteoblasts in the living body and the material are integrated to cause bone adhesion.However, such a material is mainly semi-luxed and compared with living bone tissue. It has the disadvantage that the strength is relatively low, and that if the surface of the material is scratched, the strength is extremely reduced. On the other hand, bioactive materials such as metal materials, carbon materials, alumina, and zirconia are better in strength than living bone tissue, but are inferior to bioactive materials in adhesion to living bodies. Therefore, in order to improve such adhesiveness, the surface of the material is provided with irregularities, or a porous structure layer is provided on the surface of the material so as to form a connective tissue similar to that of a living body, and strong adhesiveness is generated by a reaction with the living body. A method (Japanese Patent Publication No. 61-9859) and the like are known. [Problems to be Solved by the Invention] However, although such a bioactive material or a bioinert material has respective characteristics in adhesion to a living body,
The period for completing such bonding is about 2 ~
It takes a long period of three months, and it is necessary to keep the artificial prosthetic material in the implanted part for such a period. And if the standing and holding is insufficient, the period required for bonding is further extended,
Alternatively, there has been a problem that adhesion becomes impossible due to inflammation or the like. [Means for Solving the Problems] Accordingly, the present inventors have conducted intensive studies in order to solve such problems, and as a result, cell proliferation and cell growth in the surface layer of the artificial prosthesis material having a specific structure. The present inventors have found that by including a substance that promotes differentiation, bone formation is promoted, and the period required for adhesion between a living body and an artificial material can be significantly shortened. That is, an object of the present invention is to provide a prosthetic prosthetic material having a high property, in which bone formation is easy and the bonding period can be shortened. The purpose is an artificial prosthetic prosthesis material having a porous structure layer substantially composed of a carbonaceous material having a thickness of 0.1 mm or more on the surface of a base material, and the porous structure layer is formed by randomly forming fine single fibers. It is composed of the arranged fibrous material and pyrolytic carbon deposited on it, and the average pore size on the surface is about
It is a structure having a porosity distribution such that the porosity gradually decreases toward the substrate side at 100 μm or more, and characterized in that the cell growth / differentiation promoting substance is dispersed and contained in the porous structure layer. This is easily achieved with an artificial prosthetic material. Hereinafter, the present invention will be described in detail. The artificial prosthetic material used in the present invention has a specific porous structure layer on its surface. Specifically, it is an artificial prosthetic prosthesis material having a porous structure layer substantially composed of a carbon material having a thickness of 0.1 mm or more on the surface of a base material, and the porous structure layer has fine single fibers randomly arranged. Fibrous material and pyrolytic carbon deposited on it, and the average pore size on the surface is about 10
It is a structure having a porosity distribution such that the porosity gradually decreases toward the substrate at 0 μm or more. Hereinafter, the artificial prosthetic material having the specific structure will be described. The meaning of the porous structure layer is a general term for a surface structure having a high porosity, in which fibers are generally deposited and bound to each other, thereby forming many voids. Refers to the surface structure, and there are many different shapes depending on the thickness, length, shape, amount and orientation of the fiber and the degree of binding. Typically, for example, it refers to a structure in which a large number of fibers are overlapped in a random direction and are firmly bound to each other. The size of the formed hole includes a surface portion having a hole diameter of 100 μm or more, preferably 200 μm or more, and preferably has a shape in which the hole diameter decreases toward the inside. Generally, the prosthetic prosthesis material must have sufficient elasticity and strength to withstand considerable impact forces. In response to such demands, the presence of the porous structure layer of the present invention and the gas phase pyrolytic carbon deposited thereon exhibit extremely effective performance. That is, the artificial prosthetic material is extremely tough because it is coated with gas-phase pyrolytic carbon itself, and when embedded in a living body, living tissue penetrates into the pores of the porous structure layer, and The connective tissue invaded by the three-dimensional structure and the bone dielectric action of carbon is calcified and turned into bone tissue. For this reason, the carbon fiber and the living tissue form a double network structure entangled with each other, and are firmly bonded and fixed to the living body. Then, in order to produce such an artificial prosthetic material, first, a carbon material, specifically, various carbon fiber reinforced carbon materials,
A sintered carbon material or a vitreous carbon material, or a metal material, specifically, platinum, titanium, tantalum, tungsten, or the like, is appropriately shaped into, for example, a bar, a plate, a blade, or a required shape. In the case of metal, if necessary, a carbon film is formed on the surface by means such as a physical carbon vapor decomposition method as a base material, and this surface is advantageous for forming a porous structure layer with appropriate fibers. Cover in shape. As the material of the fiber used, for example, the above-described carbon metal of the base material, and as the shape thereof, a woven fabric, a nonwoven fabric, a felt paper, and a relatively short fiber chopped strand using relatively long fibers are used. Can be In order to coat the substrate surface with these fibers, in the case of knitted fabrics, nonwoven fabrics, felts, papers, etc., cut them into appropriate sizes and attach them using an organic adhesive as necessary, and furthermore, if necessary. Wound with a long fiber and fixed. When a chopped strand is used, a method is used in which an organic adhesive is applied to a necessary portion of the surface of the base material, and the chopped strand is adhered to the organic adhesive. Various methods have been described above for coating the surface of the base material with the fibers. In particular, a method of coating the base material with a carbon fiber non-woven fabric and fixing it with an organic adhesive or carbon fibers as necessary is preferable. Regardless of which method is adopted, the final product is obtained by subjecting the substrate surface to a fiber layer with a high porosity and performing a subsequent pyrolytic carbon treatment,
Care should be taken to advantageously produce a porous structure layer. Next, pyrolytic carbon is deposited on the resulting material (hereinafter referred to as a material for deposition) to be integrated. In this pyrolytic carbon treatment, the temperature of the substrate is 600 ° C or higher and 2300 ° C, desirably 700 to 1100 ° C, and a state having a negative temperature gradient from the substrate to the surface is created, and the pyrolytic carbon is deposited. Rushing is important for producing an excellent carbonaceous prosthetic prosthetic material. In other words, the substrate and the fibrous material on the surface are firmly bonded and fixed, and at the same time, the inside of the fibrous material, that is, the substrate side is the densest, and has a porosity distribution such that the porosity gradually increases toward the outer surface layer. In order to form a porous structure layer, the above conditions are required. In the present invention, a cell growth / differentiation promoting substance is dispersed / contained in the porous structure layer of the artificial prosthetic material having the above specific structure in order to promote bone formation. Any substance that has osteogenic ability can be used as a cell growth / differentiation promoting substance. Specifically, bone morphogetic protein (BMP), cartilage-inducing factor (CIF) , Bone-derived growth factor (BDGF), skeletal growth factor (SGF), cartilage-derived growth factor (CDGF), cartilage-derived factor (CDF) ), Insulin, somatomedin-C platelet-derived growth factor (Platelet-
derived growth factor (PDGF), parathyroid hormone (PT
H), calcitonin, epidermal growth factor (EGF) and the like.
It is better to use more than one kind. These substances are dispersed and mixed in physiological saline or the like in advance and impregnated into the porous layer of the artificial prosthetic prosthesis material or attached to the layer to form the artificial prosthetic prosthesis material of the present invention. Prepare. The cell growth / differentiation promoting substance need only be contained in the porous layer in a substantially dispersed state, and need not be particularly uniformly dispersed. The amount of the above substances is not particularly limited,
Usually, it is used in an amount of 0.001 part by weight or more, preferably 0.01 to 0.1 part by weight, per 100 parts by weight of the material. Further, if necessary, the porous layer is subjected to a surface treatment with a hard protein such as collagen in advance, and then a cell proliferation promoting substance is dispersed and contained therein, so that the substance hardly flows out of the porous layer. Good. As a surface treatment method using a hard protein such as collagen, a known method is used.For example, the artificial prosthetic material is immersed in a solution of collagen or a solution in which denatured collagen is dispersed, and then freeze-dried at a low temperature. In some cases, it is more preferable to use a solution in which a cell growth promoting substance is dispersed in the collagen solution because the operation becomes easier. EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples. Example 1 A carbon fiber felt was wound around the surface of a carbon fiber reinforced carbon composite material having a diameter of 3.5 mm and a length of 80 mm (hereinafter referred to as “C / C composite material”) ((1) in FIG. 1). 0.8 mm. This C / C composite material is heated to 700 ° C in the reactor by induction heating.
Then, dichloroethylene vapor is introduced into the reactor using Ar gas as a carrier gas to generate pyrolytic carbon. After the reaction for 4 hours, a material having a porous structure layer ((2) in FIG. 1) in which the surface is open pores is obtained by integrating the C / C composite material and the carbon fibers by bonding with pyrolytic carbon. The surface condition of this material is adjusted with a grinder for work. After that, it is cut into three pieces each having a length of 15 mm, and a hole having a diameter of 2.0 mm and a depth of 10 mm is made in one end face. A post (3) made of a titanium alloy shown in FIG. 1 is attached to the hole by bone cement to obtain an artificial prosthetic material (A). The material (A) was added to rat osteoinductive factor (BMP) (Bone-m
orphogetic protein; Proc. Natl. Acad. Sci, 75, 1828-183
2 (1979)) in a 1% by weight physiological saline solution,
Then, the artificial prosthesis material of the present invention was obtained by freeze-drying at a low temperature. Next, the material thus prepared is inserted into the lower jaw bone of a cynomolgus monkey weighing 4 kg so that the titanium alloy portion thereof faces upward, and the epithelium is sutured at one end. After one month, the incision was made again, the titanium alloy post was pulled out of the material, and the titanium alloy post (3) having a shape penetrating the epithelium shown in FIG. Glue to the material and re-suturing. A few days later, the crown is attached to the titanium alloy so that occlusal pressure is applied.
Now, after one year, inflammation and loosening
None, showing good results. Example 2 After adjusting the surface condition of a material having a porous structure layer obtained in the same manner as in Example 1 using a grinder for work, a length of 10
The prosthetic material (A) was obtained by cutting into mm units. This material (A) was immersed in a collagen solution in which 1% by weight of BMP used in Example 1 was dispersed, and an artificial prosthesis material of the present invention was obtained in the same manner as in Example 1. Next, the rod-shaped material was inserted into the middle part of the femur of a cynomolgus monkey weighing 4 kg, and removed one month later. The cross section of the porous structure layer on the surface was cut out to a thickness of 100 μm, and a microradiogram was taken using soft X-rays. As a result, it was confirmed that new bone was formed in the porous structure layer in a short period of one month. [Effects of the Invention] According to the present invention, an osteogenic reaction by a living body can be facilitated by dispersing and containing a cell growth / differentiation promoting substance in a porous layer of an artificial prosthetic prosthetic material having a specific structure. Can significantly reduce the required time.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 and 2 show examples of embodiments in which the artificial prosthetic material according to the present invention is used as a root material. 1: C / C composite, 2: Porous structure layer, 3: Titanium alloy post

   ────────────────────────────────────────────────── ─── Continuation of front page    (73) Patent holder 999999999               New Technology Agency               4-8 Honcho, Kawaguchi City, Saitama Prefecture (73) Patent holder 999999999               Mitsubishi Chemical Corporation               2-5-2 Marunouchi, Chiyoda-ku, Tokyo (72) Inventor Suguro Otani               2010-2, Kurokawa, Hishimachi, Kiryu-shi (72) Inventor ▲ Yanagi ▼ Sawakatsu Sawa               2-3-3, Mita, Minato-ku, Tokyo (72) Inventor Kunio Niijima               563 Kamikomachi, Omiya City, Saitama Prefecture (72) Inventor Kazushi Matsuura               1000 Kamoshida-cho, Midori-ku, Yokohama-shi, Kanagawa               Mitsubishi Chemical Industry Co., Ltd.                (56) References JP-A-57-134154 (JP, A)                 JP-A-61-200903 (JP, A)

Claims (1)

(57) [Claims] An artificial prosthetic material having a porous structure layer substantially composed of a carbonaceous material having a thickness of 0.1 mm or more on a substrate surface, wherein the porous structure layer is a fibrous material in which fine single fibers are randomly arranged. It is composed of a substance and pyrolytic carbon deposited thereon, and has a porosity distribution such that the average pore diameter at the surface thereof is about 100 μm or more and the porosity gradually decreases toward the substrate side, and Cell proliferation in the structural layer
An artificial prosthetic material comprising a differentiation promoting substance dispersed and contained therein. 2. Cell growth / differentiation promoting substances are osteoinductive factor, cartilage inducing factor, bone derived growth factor, skeletal growth factor, cartilage derived growth factor, cartilage derived factor, insulin, somatomedin-C, platelet derived growth factor, parathyroid hormone, calcitonin,
2. The prosthetic prosthetic material according to claim 1, wherein the prosthetic material is at least one substance selected from epidermal growth factor. 3. 2. The prosthetic prosthetic material according to claim 1, wherein the base material is a carbon or metal material.