JP5232483B2 - Biological implant - Google Patents

Description

  The present invention relates to a bioimplant, and in particular, has a mechanical property close to that of a bone or a tooth, and has a function of combining with a bone when the bioimplant is embedded in the body, and is highly safe with respect to the living body. About.

  As a treatment method when a bone is largely lost, autologous bone transplantation in which a part of a patient's own normal bone is cut out and transplanted to an affected part, or an artificial bone transplantation in which an artificial bone made of an artificial material is transplanted is performed. However, autologous bone transplantation limits the amount of bone that can be collected and damages normal cells, so the burden on the patient is heavy and the bone for autologous bone transplantation used for autologous bone transplantation is the patient's own. Since a new defect is generated by cutting from a normal bone, it cannot be said to be an essential treatment method when the bone is largely lost. Artificial bone transplantation uses industrially produced artificial bone, so there is no problem like autologous bone transplantation, but the mechanical and biological characteristics of the artificial bone differ from the original bone. There is a problem that the use is limited according to the above-mentioned characteristics. For example, when a titanium alloy metal material is selected as the artificial bone material, the metal material is usually high in strength, but has a high modulus of elasticity and lacks toughness. Then, there is a problem that stress shielding occurs due to a difference in mechanical characteristics with surrounding bones, and a problem that it does not directly bond to bones. In addition, when bioceramics such as hydroxyapatite are selected as the material for the artificial bone, the bioceramics usually have good biocompatibility, high bioactivity, and excellent bone binding properties, but external Since it is vulnerable to impact, there is a problem that it cannot be used for a part where a large load is applied instantaneously. When a polymer such as ultrahigh molecular weight polyethylene is selected as the material for the artificial bone, the problems of metal materials and bioceramics can be solved. In particular, among the polymers, polyether ether ketone (PEEK) has mechanical properties. Since it is close to the original bone and excellent in biocompatibility, it is expected to be applied as an orthopedic material in a site where high strength is required. Furthermore, artificial bones that are directly bonded to bones have been developed by combining polymers and bioceramics having biological activity.

  Claim 1 of Patent Document 1 describes "An orthopedic composition comprising a homogeneous mixture of a biocompatible polymer and a bioactive particulate ceramic having an average particle size of about 500 nm." “The increase in the surface area of the particles and the interaction of the particles with various polymers will provide a composition with favorable biological and mechanical properties.” However, studies on the toxicity of nanoscale particles to living bodies have been conducted in recent years, and it is suggested that nanoscale particles may cause inflammation even if they are biocompatible substances. Yes. The orthopedic composition shown in the example of Patent Document 1 is formed by a biocompatible polymer such as PEEK that does not chemically bind to bioactive fine particles and hydroxyapatite nanoparticles having an average particle size of 500 nm or less. When the pellet formed from this orthopedic composition is embedded in a living body, it is easily estimated that the bioactive fine particles on the surface of the pellet are detached and the detached nano There is a concern that scale particles may adversely affect the living body. In addition, in the orthopedic composition presented in Patent Document 1, even when the bioactive fine particles are not detached alone and contribute to chemical bonding with bones of the living body, the bioactive fine particles themselves There is a possibility that the expected fixing force with the biocompatible polymer as the base material may not be expressed.

Japanese translation of PCT publication No. 2004-521685

  An object of the present invention is to provide a biological implant that has mechanical properties close to bones or teeth, has a function of combining with a bone when the biological implant is embedded in the body, and has high safety to the living body. That is.

As means for solving the problems,
Claim 1
A bioimplant in which a bioactive member is mixed with a plastic member as a matrix that has strength characteristics close to those of living bones and is non-absorbable and non-degradable in vivo, and a part of the bioactive member is plastic Exposed to the surface of the member, wherein the bioactive member has a long axis-containing shape, and an average long axis length in the shape of the bioactive member is 5 to 100 μm,
Claim 2
The bio-implant according to claim 1, wherein the plastic member is formed of polyetheretherketone.
Claim 3
The bioactive member according to claim 1 or 2, wherein the bioactive member is formed of a calcium phosphate compound.
Claim 4
The biological implant according to any one of claims 1 to 3, wherein the calcium phosphate compound is hydroxyapatite.

  The bioimplant according to the present invention is formed by mixing a bioactive member with a plastic member that has strength characteristics close to those of a living bone and is non-absorbable and non-degradable in vivo. A part of the bioactive member is exposed on the surface of the plastic member. And the said bioactive member has a long axis containing shape, and the average long axis length is 5-100 micrometers. Here, the term long axis containing shape means the shape of the bioactive member. The major axis-containing shape is a shape having a length that is always determined as the major axis when the shape of the bioactive member is measured. Furthermore, when the length of the bioactive member is measured along an arbitrary direction, the direction having the maximum length is always found. As for the long axis length in the long axis containing shape, when a minimum rectangular parallelepiped space that accommodates the bioactive member is assumed, the maximum length side in the rectangular parallelepiped space is referred to as the long axis length. From this definition, the long axis-containing shape does not include a sphere or a substantially spherical shape. Specific examples of the long axis-containing shape include, for example, a rod shape, a needle shape, a fiber shape, a plate shape, an oblong shape, and an oblate shape. Therefore, the living body implant according to the present invention is formed of a plastic member having strength characteristics similar to living bones and is non-absorbable and non-degradable in the living body. Even in this case, the strength corresponding to the strength characteristic of the bone at the application site can be maintained. Moreover, in the living body implant which concerns on this invention, since the bioactive member is exposed on the surface of the living body implant, it has a function which the exposed living body implant and living body bone couple | bond. In addition, since the bioactive member has the long axis-containing shape, the fitting force with the plastic member is physically increased, so that the bioactive member can be prevented from dropping from the surface of the bioimplant. When the average major axis length in the shape of the bioactive member is within the above range, the bioactive member should be detached from the surface of the bioimplant after the bioimplant according to the present invention is embedded in the living body. However, it is possible to prevent such an adverse effect that the bioactive member formed by the nanoscale particles exerts on the living body. Therefore, it is possible to provide a biological implant that has mechanical properties close to bones or teeth, has a function of binding to a bone when the biological implant is embedded in the body, and has high safety to the living body.

  When, for example, polyetheretherketone is used as a material for forming the plastic member, polyetheretherketone has biocompatibility that is close to that of bone or teeth, so that this bioimplant can be attached to bone. Stress shielding, i.e., the bone loss and bone density that can occur due to shielding of the stress applied to the bone when it is applied as an artificial bone to a site where coupling is required and a large load is continuously applied over a long period of time It is possible to provide a high-strength biological implant that does not cause a decrease or the like.

  In addition, if the substance forming the bioactive member is, for example, a calcium phosphate compound, particularly hydroxyapatite, since hydroxyapatite is an actual inorganic component of bone, hydroxyapatite is exposed on the surface of the bioimplant. For example, a chemical reaction between the hydroxyapatite and the bone tissue of the living body starts, and new bone is rapidly formed, so that the bone and the living body implant can be bonded at an early stage.

  First, with reference to FIG. 1, the structure of the biological implant which is one Example of this invention is demonstrated. As shown in FIG. 1, a biological implant 1 according to the present invention includes a bioactive member 3 mixed with a plastic member 2 having strength characteristics close to those of a living bone and being non-absorbable and non-degradable in vivo. In the bioimplant 1, a part of the bioactive member 3 is exposed on the surface of the plastic member 2, and the bioactive member 3 has a long axis-containing shape, for example, a rod shape, a needle shape, a fiber shape, a plate shape, and an oval shape. , And at least one shape selected from the group consisting of oblate balls, and the average major axis length in the shape of the bioactive member 3 is 5 to 100 μm.

  The bioimplant 1 according to the present invention includes a plastic member 2 and a bioactive member 3, and a part of the bioactive member 3 is exposed on the surface of the plastic member 2. The area ratio of the bioactive member 3 exposed on the surface with respect to the surface area of the biological implant 1 is preferably 0.5 to 50%, and more preferably 10 to 40%. When the bioactive member 3 is exposed on the surface of the living body implant within the above range, the chemical reaction between the substance forming the bioactive member and the bone tissue of the living body after the living body implant 1 is embedded in the living body. Since the formation of new bone is triggered by the substance forming the bioactive member, it is possible to provide the bioimplant 1 that can combine the bone and the bioimplant.

  The ratio of the area of the bioactive member to the surface area of the bioimplant is 2 for the bioactive member and other parts by using the image analysis software (Scion Image) obtained by photographing the surface of the bioimplant with a scanning electron microscope. By digitizing, the area ratio of the bioactive member to the area of the entire photograph can be calculated and obtained.

  The bioactive member 3 is preferably uniformly distributed in the plastic member as a matrix. When the bioactive member 3 is uniformly distributed in the plastic member, the bioactive member 3 is exposed on the newly formed surface of the bioimplant 1 even if it is cut at any cross section of the bioimplant 1. be able to. Therefore, the biological implant 1 having a certain shape can be manufactured, and the biological implant 1 having the necessary size and shape can be cut out and used when necessary. Moreover, as another form, it is preferable that the density of the bioactive member 3 in the surface part vicinity is higher than the center part of the bioimplant 1. When the density of the bioactive member 3 in the vicinity of the surface portion is higher than the center portion of the bioimplant 1, the bioactive member 3 is exposed on the surface of the bioimplant 1 and the bioactive member 3 is high in the vicinity of the surface portion. When present at a density, the substance that forms this bioactive member becomes a trigger to easily form new bone, and therefore, it is possible to provide the bioimplant 1 capable of binding the bone and the bioimplant at an early stage. .

  The volume ratio of the bioactive member 3 to the biological implant 1 is preferably 10 to 50%, and more preferably 20 to 40%. In the case where the volume ratio of the bioactive member 3 is within the above range, the material has mechanical properties close to bones or teeth and forms the bioactive member after the bioimplant is embedded in the living body. Since the chemical reaction between the bone tissue and the living bone tissue begins and the formation of new bone is triggered by the substance that forms this bioactive member, it is possible to bond the bone and the biological implant with high strength. A biological implant can be provided.

  The volume ratio of the bioactive member contained in the bioimplant can be obtained in the same manner as the above-described method for measuring the ratio of the bioactive member to the surface area of the bioimplant. That is, the area ratio of the bioactive member in the cross section of the bioimplant can be calculated at a plurality of locations, and the volume ratio of the bioactive member can be estimated from the arithmetic average of these calculated values.

  The bioactive member 3 has a long axis-containing shape, and has, for example, at least one shape selected from the group consisting of a rod shape, a needle shape, a fiber shape, a plate shape, an oblong shape, and an oblate shape. FIG. 1 is an example of a biological implant 1 when the bioactive member 3 has a rod-like shape. Since the fitting force between the bioactive member 3 and the plastic member 2 is physically enhanced when the bioactive member 3 has the shape when the bioimplant according to the present invention is embedded in the body, the surface of the bioimplant 1 Therefore, it is possible to provide the biological implant 1 that can prevent the bioactive member 3 from falling off.

  When the shape of the bioactive member 3 is a rod shape, as shown in FIG. 2A, for example, it can be expressed as a rectangular column of length × width × height A × B × L, for example, A and B Cube with the same length of L and L, A square column with the same length of A and B and L is longer than A and B, and a square column with different lengths of A, B and L are also included in the rod It is. As shown in FIG. 2B, when the lengths of A and B are different, the shape of the bioactive member 3 can also be referred to as a plate shape. In the present invention, it is not necessary to strictly distinguish whether the shape of the bioactive member 3 is a rod shape or a plate shape. When the shape of the bioactive member 3 is a rod shape, the cross section perpendicular or horizontal to the long axis direction L is a quadrangle as shown in FIGS. 2 (a) and 2 (b). It is not limited, and the case where the cross section is a polygon such as a circle, an ellipse, a triangle, and a hexagon is also included. The bioactive member 3 having the shape shown in FIGS. 2A and 2B can be referred to as a rod shape, a needle shape, or a fiber shape depending on the difference in the value of A or B and L. However, in the present invention, it is not necessary to strictly distinguish whether the shape of the bioactive member 3 is a rod shape, a needle shape, or a fiber shape due to the difference in the ratio values. Further, when the shape of the bioactive member 3 according to the present invention is oblong, as shown in FIG. 2 (c), the major axis diameter is L, the minor axis diameter is C, and the major axis is the axis. Can be expressed as a long sphere produced by rotating. When the shape of the bioactive member 3 according to the present invention is oblate, the major axis diameter is L, the minor axis diameter is D, and the minor axis is the axis as shown in FIG. Can be expressed as oblate spheres produced by rotation.

  The average major axis length in the shape of the bioactive member 3 is 5 to 100 μm, and preferably 10 to 50 μm. The long axis length is an axial length having at least the longest dimension of the bioactive member 3 that is independently formed. For example, FIG. 2A to FIG. In FIG. 2D, the major axis length corresponds to the length L. When the arithmetic average of the major axis lengths of the plurality of bioactive members 3 included in the biological implant is calculated, the average major axis length can be obtained. When the average major axis length in the shape of the bioactive member 3 is within the above range, the bioactive member should be detached from the surface of the bioimplant after the bioimplant according to the present invention is embedded in the living body. Even if it is a case, since the bad influence which the bioactive member formed with a nanoscale particle exerts on a biological body can be prevented, the biological implant with high safety | security with respect to a biological body can be provided.

The substance forming the bioactive member is not particularly limited as long as it has a high affinity with the living body and has a property of chemically reacting with bone tissue including teeth. For example, calcium phosphate compound, bioglass, crystallization Examples thereof include glass (also referred to as glass ceramics), calcium carbonate, and the like. Examples of calcium phosphate compounds include calcium hydrogen phosphate, calcium hydrogen phosphate hydrate, calcium dihydrogen phosphate, calcium dihydrogen phosphate hydrate, α-type tricalcium phosphate, β-type tricalcium phosphate, dolomite , Tetracalcium phosphate, octacalcium phosphate, hydroxyapatite, fluorapatite, carbonate apatite, and chlorapatite. Examples of the bioglass include SiO ₂ —CaO—Na ₂ O—P ₂ O ₅ glass, SiO ₂ —CaO—Na ₂ O—P ₂ O ₅ —K ₂ O—MgO glass, and SiO ₂ —. Examples include CaO—Al ₂ O ₃ —P ₂ O ₅ glass. Examples of the crystallized glass include SiO ₂ —CaO—MgO—P ₂ O ₅ glass (also referred to as apatite wollastonite crystallized glass), CaO—Al ₂ O ₃ —P ₂ O ₅ glass, and the like. Is mentioned. These calcium phosphate compounds, bioglass, and crystallized glass are described in, for example, “Chemical Handbook Applied Chemistry 6th Edition” (The Chemical Society of Japan, published on January 30, 2003, Maruzen Co., Ltd.), “Development of Bioceramics and “Clinical” (edited by Hideki Aoki et al., Published on April 10, 1987, Quintessence Publishing Co., Ltd.) and the like.

  Among these, as a substance that forms a bioactive member, a calcium phosphate compound is preferable in terms of excellent bioactivity, and since the composition, structure, and properties are similar to actual bones, the stability in the body environment is excellent. Hydroxyapatite is particularly preferred because it does not show significant solubility in the body.

  The bioactive member 3 has a long axis-containing shape, for example, a rod shape, a needle shape, a fiber shape, a plate shape, an oblong shape, or an oblate shape, and an average long axis length in the long axis-containing shape is 5 to 100 μm. As long as the active member 3 can be obtained, it can be produced by any method. For example, a bioactive member formed of a calcium phosphate compound is obtained by mixing a solid calcium compound and a solid phosphorus compound at 1,000 ° C. By using the solid phase method of heating, the hydrothermal method of growing crystals in a high temperature aqueous solution using an autoclave, the method of extruding and sintering a calcium phosphate compound mixed with a binder, etc. Can be manufactured.

  As a fibrous calcium phosphate compound, for example, as a method for producing an apatite whisker, a calcium phosphate gel compound that generates orthophosphoric acid and proton at 80 to 250 ° C. is dispersed in a solvent containing at least one of water and a hydrophilic organic solvent. A dispersion step for obtaining a dispersion, and a heating step for heating the dispersion to 80 to 250 ° C. in a sealed container, the pH of the dispersion before heating is set to 10 or less, and the dispersion after heating is A method of manufacturing by adjusting the pH to 3.9-9 can be adopted.

  The calcium phosphate gel compound may be a calcium-containing compound that generates orthophosphoric acid and protons at 80 to 250 ° C., and condensed calcium phosphate gel compounds such as calcium pyrophosphate gel, tripolycalcium phosphate gel, and hexametaphosphate calcium gel are also used. You can also.

  Examples of the hydrophilic organic solvent include organic solvents that are soluble or miscible in water. Examples thereof include lower alcohols having 1 to 3 carbon atoms such as methanol and ethanol, dimethyl ether, diethyl ether, and methyl ethyl. Examples include ethers such as ether, and water-soluble ketones such as acetone.

  When a lower alcohol is used as a solvent in the dispersion step, the pH of the dispersion after heating can be adjusted to 3.9 to 9 simply by dispersing the calcium phosphate gel compound in the lower alcohol, so the pH of the dispersion is further adjusted. This is convenient because it is not necessary.

  When the lower alcohol is employed as the solvent, 2-propanol is preferable among the lower alcohols. When 2-propanol is used as a solvent, the pH control effect can be exerted with a small addition amount, and therefore, pH adjustment before and after heating can be more easily performed than other solvents.

  In the dispersion step, any one of water and a hydrophilic organic solvent can be used alone, or the above two kinds can be used in combination. When a mixture of water and a hydrophilic organic solvent is used as the solvent, the concentration of the hydrophilic organic solvent with respect to the mixture is preferably, for example, 60% by volume or less, particularly 50% by volume or less.

  As content of the calcium-phosphate gel compound with respect to a dispersion liquid, 0.1-20 mass parts with respect to 100 mass parts of dispersion liquid, Preferably 0.5-15 mass parts can be mentioned. When the content of the phosphoric acid gel compound is within the above range, an apatite whisker can be preferably produced.

  When the calcium phosphate gel compound is mixed with a solvent containing at least one of water and a hydrophilic organic solvent, the molar ratio of calcium atoms to phosphorus atoms (Ca / P) in the dispersion is 0.5 to 2.0. In particular, it is preferable to adjust to 1.4 to 1.8. In addition to the calcium phosphate gel compound, calcium salts that generate Ca ions, phosphates that generate phosphate ions, and the like are separately added to match the molar ratio (Ca / P) of the finally obtained apatite whiskers. Also good. In this case, the molar ratio is preferably adjusted to 1.4 to 1.8. That is, the abundance of these ions need not match the Ca / P molar ratio of the composition of the calcium phosphate gel compound, and may be in excess. Furthermore, in order to control the composition of the apatite whisker, a compound that supplies carbonate ion, fluorine ion, chloride ion, cation, etc. is added separately, and the calcium ion site, phosphate ion site and Each ion can also be introduced into the hydroxide ion site.

  It is important to adjust the pH of the dispersion to 10 or less before performing the reaction in the heating step. When the pH of the dispersion exceeds 10, it becomes fine apatite whiskers, whereas when the pH of the dispersion before heating is 10 or less, the major axis length of the obtained apatite whiskers is as large as 5 μm to 100 μm. A whisker is obtained. In order to adjust the pH before heating, it is preferable to add a pH adjusting agent. In addition, in combination with adjusting the pH to 10 or less, the addition of titanium oxide can suppress the formation of calcium hydrogen phosphate, and further has an effect of promoting whisker growth.

  In the heating step, the dispersion having a pH adjusted to 10 or less obtained in the dispersion step is heated to 80 to 250 ° C., and the pH of the dispersion after the heating is set to 3.9 to 9 Adjust to.

  The lower the heating temperature, the slower the growth rate of the whiskers, so the major axis length of the apatite whiskers becomes shorter.

  When the dispersion is heated, the pH of the dispersion may decrease. In that case, the pH of the dispersion is adjusted to 3.9-9 by adding a pH adjuster to the dispersion. By adjusting the pH of the dispersion to 3.9 to 9, an apatite whisker having an average major axis length in the range of 5 to 100 μm can be obtained.

  As the pH adjuster, the same pH adjuster as that used in the dispersion step can be used, for example, an inorganic acid such as nitric acid or hydrochloric acid, an organic acid such as acetic acid, ammonia or hydroxylation. Examples thereof include alkalis such as sodium, urea which decomposes by hydrothermal treatment and releases alkalis, and hydrochloric acid and nitric acid are particularly preferable. Urea is also preferred as a pH adjuster. When urea is used, it is possible to neutralize protons that are decomposed as the temperature rises due to hydrothermal treatment and proceeds with the progress of the apatite formation reaction, and the pH of the dispersion can be easily controlled by the carbonate ions that are produced. Further, carbonate ions generated by the decomposition of urea are taken into the apatite to form a carbonate-containing apatite. Carbonate-containing apatite has a higher rate of absorption in vivo than hydroxyapatite that does not contain carbonate, and is useful as an in-vivo replacement material. Moreover, the aspect ratio of the apatite whisker obtained can be easily controlled by adjusting the concentration of the urea dispersion to be added.

  The dispersion is preferably heated in a pressure-tight airtight container so that the volume of the solvent does not decrease. The heating time of the dispersion is usually 1 to 48 hours.

  When the heating of the dispersion liquid is completed, apatite whiskers are generated in the resulting product liquid. Since the apatite whisker exists in the liquid, the whisker can be taken out by separating the whisker by filtration, centrifugation, or the like, and the whisker can be taken out after drying. However, the separation / drying method is not particularly limited. Further, the whisker may be washed simultaneously with the separation or after the separation.

  The biological implant 1 according to the present invention is formed of a plastic member 2 and a bioactive member 3 that have strength characteristics close to those of living bones and are non-absorbable and non-degradable in vivo. Examples of the evaluation items as to whether or not the plastic member 2 has strength characteristics similar to those of living bones include elastic modulus, bending strength, compressive strength, and tensile strength. The meaning of the strength characteristic close to living bones is that the value of the evaluation item is the same as the value of bone or tooth, or has a value close enough to cause no problem. For example, as an evaluation item that the strength characteristics are close to bones or teeth, an elastic modulus is 10 to 50 GPa and a bending strength is 100 MPa or more.

  The plastic member 2 that is non-absorbable and non-degradable in the living body is a plastic member 2 that is hardly absorbed or decomposed in the living body when the plastic member 2 is embedded in the living body, and does not hinder the object of the present invention. The plastic member 2 that may be absorbed or decomposed in the living body is included as long as it is within the range. By adopting the non-absorbable and non-decomposable plastic member 2 in the living body, the desired strength can be maintained even when the living body implant 1 is embedded in the living body for a long period of time.

  When the living body implant 1 according to the present invention is applied as a substitute bone for a portion where a large load is applied continuously for a long period of time, a plastic having a high elastic modulus and bending strength is preferable as the material forming the plastic member. Engineering plastics, for example, polyamide, polyacetal, polycarbonate, polyphenylene ether, polyester, polyphenyline oxide, polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyethersulfone, polyphenylene sulfide, polyarylate, polyetherimide, polyether Ether ketone, polyamide imide, polyimide, fluorine resin, ethylene vinyl alcohol copolymer, polymethylpentene, phenol resin, Carboxymethyl resin, silicone resin, diallyl phthalate resin, polyoxymethylene, polytetrafluoroethylene and the like.

  Examples of the material forming the plastic member include polyethylene, polyvinyl chloride, polypropylene, EVA resin, EEA resin, 4-methylpentene-1 resin, ABS resin, AS resin, ACS resin, methacrylic, in addition to the engineering plastics. Acid methyl resin, ethylene vinyl chloride copolymer, propylene vinyl chloride copolymer, vinylidene chloride resin, polyvinyl alcohol, polyvinyl formal, polyvinyl acetoacetal, polyfluorinated ethylene propylene, polytrifluoroethylene chloride, methacrylic resin, linole resin, Polyallyl ether ketone, polyketone sulfide, polystyrene, polyaminobismaleimide, urea resin, melamine resin, xylene resin, isophthalic acid resin, aniline resin, furan resin, polyurethane Alkylbenzene resin, guanamine resin, poly ether resins.

  Since the bioimplant 1 according to the present invention is formed of the plastic member 2 and the bioactive member 3, the strength characteristics of the bioimplant 1 depend on the mixing ratio and distribution state of the bioactive member 3 to the plastic member 2. Change. Therefore, the type of plastic can be appropriately selected so that the biological implant 1 can obtain desired strength characteristics according to the bone or tooth of the application site.

  Among these, polyether ether ketone (PEEK) is particularly preferable as the material forming the plastic member. Since PEEK has biocompatibility, has strength characteristics similar to those of living bones, and is a non-absorbable and non-degradable plastic in vivo, when PEEK is adopted as a material forming a plastic member, a large load is applied. When this bio-implant is embedded in a site that takes a long time continuously, it does not cause stress reduction, i.e., bone loss and bone density reduction that may occur due to shielding of stress applied to the bone. A strong bioimplant can be provided.

  Also, in the materials forming the plastic member, if necessary, color stabilizers such as antistatic agents, antioxidants, hindered amine compounds and other light stabilizers, lubricants, antiblocking agents, ultraviolet absorbers, inorganic fillers, pigments, etc. , Etc. may contain various additives.

  The living body implant according to the present invention can be manufactured by a known method used for manufacturing a fiber reinforced plastic, for example.

  The biological implant according to the present invention is prepared by, for example, preparing a raw material for molding in which a bioactive member such as an apatite whisker manufactured by the above method and a plastic such as PEEK are mixed in advance, and this is compression-molded with a mold. It can be produced by a method, a method in which a bioactive member is laid on a mold and multiple layers are produced while defoaming the plastic, a method in which plastic is injected into a mating die in which the bioactive member is spread, and the like.

  The living body implant according to the present invention is used in various shapes, for example, a block shape, a film shape, and the like according to the use site in the living body. Preferably, the shape similar to the shape of the bone defect portion or the tooth defect portion or the like, or the shape corresponding to the shape of the bone defect portion or the tooth defect portion, etc. to which the living body implant is compensated, for example, a similar shape, Used after being shaped and / or prepared.

  The bioimplant according to the present invention can be produced in advance in a desired shape, but since the bioactive member is uniformly dispersed in the bioimplant, it can be cut in any cross section, The bioactive member can be exposed on the newly formed surface of the bioimplant. Therefore, a biological implant having a predetermined shape can be manufactured, and a biological implant having a necessary size and shape can be cut out and used when necessary.

  The biological implant according to the present invention can be applied to bone filling materials, artificial hip joints, osteosynthesis materials, artificial vertebral bodies, interbody spacers, vertebral body cages, skull substitutes, artificial tooth roots, and the like.

FIG. 1 is a schematic view of a biological implant that is one embodiment of the present invention. FIG. 2A and FIG. 2B are schematic views showing an example of the shape of the bioactive member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Bioimplant 2 Plastic member 3 Bioactive member

Claims (4)

A bioimplant in which a bioactive member is mixed with a plastic member as a matrix that has strength characteristics close to those of living bones and is non-absorbable and non-degradable in vivo, and a part of the bioactive member is plastic A bioimplant that is exposed on a surface of the member, wherein the bioactive member has a shape containing a long axis, and an average long axis length of the bioactive member is 5 to 100 μm.   The living body implant according to claim 1, wherein the plastic member is made of polyetheretherketone.   The biological implant according to claim 1 or 2, wherein the bioactive member is formed of a calcium phosphate compound.   The living body implant according to any one of claims 1 to 3, wherein the calcium phosphate compound is hydroxyapatite.

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