DE3243861A1 - Endoprosthesis of carbon fibre-reinforced material - Google Patents

Abstract

Endoprosthesis consisting of carbon fibre-reinforced composite material whose matrix material contains polyphenol glycidyl ether and 4,4'-diaminodiphenyl sulphone. Prostheses of this type may be replacements for bones and teeth, as well as boneplates and joint prostheses. The material is distinguished by its tolerability by the body.

Description

Endoprosthesis made from carbon fiber reinforced material

The invention relates to an endoprosthesis made of carbon fiber reinforced Material.

Endoprostheses serve as implants for those who are sick or damaged Bones to restore their functions.

The aim of developing endoprostheses is to manufacture implants, which is operated on the patient during his lifetime a safe and functional Provide support without having to be replaced.

Complex interactions, especially biological and physical However, factors inhibit development. These factors are the Body compatibility of the material of the implants coming into contact with the tissue, the strength and the frictional properties of articulated prosthetic parts.

Functional implants have been developed on the basis of intensive studies which consist of a plastic-metal combination construction. For ventilation joints For example, a prosthesis model consists of a combination of an elevator link from a cobalt-chrome Molybdenum leying and a hip joint socket made of high molecular weight polyethylene. The hip head is made by means of a metallic prosthesis shaft held. The attachment of this shaft as well as that of the plastic pan in the prepared bone cavities are made using self-hardening bone cement body-friendly material. This combination made it possible to compare to the previous ones common methods or implants, significant successes can be achieved. Disadvantageous the lack of compatibility of the Modulus of elasticity of bone and implant.

Loosening or breaking of the shaft are the result.

By using carbon fiber reinforcements, the strength values are favorably influenced by implants. Previous results in this area however, lack of sufficient body tolerance, which also leads to a premature loosening of the implant.

The invention is based on the object of providing endoprostheses of the initially mentioned mentioned type to the effect that they are well tolerated by the body and high resilience, the greatest possible long-term functionality own.

The object is achieved according to the invention in that the carbon fibers in a matrix of polyphenol glyci dyl ether and 4,4'-diamino-diphenyl sulfone are embedded.

It has been found that such an implant is a good one Has body tolerance and can be operated on without cement, so that the direct connection a growing together between bone and implant and consequently enables a permanent connection. With appropriate design of the density and The orientation of the fibers increases both rigidity and strength adapted to the requirements.

The prosthesis according to the invention is suitable for bone replacement for Bone parts of the entire skeleton that have been damaged in some way or had to be removed because of a tumor.

It is also provided that the endoprosthesis according to the invention for bone plates as well as the associated screws.

The prosthesis can also be used for dentures, especially as a pin tooth use.

An important application is the field of gel theses, being according to an embodiment of the invention in the joint of the fiber composite material with ceramic (Al 203) works together. This ensures that the artificial joint works together without significant abrasion. The joint socket is preferably made of fiber composite material according to claim 1 and the joint ball made of ceramic.

The joint head made of ceramic is preferably made of a shaft with a 9 m composite material, corresponding to the joint socket, long fibers in particular are used.

Such a shaft can be made by appropriate fiber orientation design in such a way that the moduli of elasticity of the bone and shaft are compatible given is. This is a further contribution to extending the service life given by counteracting loosening of the prosthesis in the bone.

In the event of excessive stress, such as a fall of the prosthesis wearer the joint head may be damaged. To be able to use in such cases to be able to repair the damage with a quick and minor surgical procedure provided that the joint head on one end protruding from the joint bone of the prosthesis shaft is detachably attached. As a result, the prosthesis socket needs not to be detached from the bone if the joint head is damaged, instead, only the joint head is exchanged.

In the plug connection is according to a further embodiment of the Invention of an elastomer made of polyether urethane provided to relieve the Prosthesis shaft largely absorbs the impact energy from the joint head.

A polyether urethane made from toluene diisocyanate can advantageously be used for this purpose and polytetramethylene ether glycol can be used with 3, 3'-dichloro-4, 4 '-diaminodiphenylmethane is cured at 100 etc for about 3 hours. The hardening process can be carried out directly as required be done on the shaft end or separately.

The invention extends to a by the features of claim 10 characterized method for producing a prosthesis.

This procedure gives the prosthesis excellent strength.

In the drawing are execution examples according to the invention shown schematically.

Fig. 1 shows a bone substitute 20, for example after a Tumor resection is inserted into a bone 21 of a locomotor member.

In Fig. 2 is a screwable to the bone plate 22 with associated Screw 23 shown.

3 shows a cheek pin tooth 24 that can be inserted in the jawbone and a cutting pin tooth 25.

All of the aforementioned implants are made of carbon fiber reinforced Composite material in which the fibers are either long fibers 26 or short fibers 27 embedded in a matrix of polyphenol glycidyl ether and 4,4'-diaminodiphenyl sulfone are.

In Fig. 4, a hip joint prosthesis is shown in the one Pelvic bone 10 a joint socket 11 is anchored. In cooperation with the A joint head 12 is provided in the socket 11, which continues with a new prosthesis socket 13 is connected for anchoring in the bone cavity 14 of the femoral shaft 15.

The gel head 12 made of Al 20 forms in conjunction with of the pan 11 from a gens cha ft afflicted with a favorable smoothness and abrasion Material qem according to the invention a largely permanent joint. The pan 11 has by bip tissue growth promoting material property also for the duration of a firm hold in the pelvic bone 10. The shaft consists of a composite material corresponding to the socket material with directed fibers 26, which give the shaft sufficient and give the bone material adapted rigidity and strength, so that also here no adverse influences with regard to the durability of the entire prosthesis be brought about. The combination of the materials of the prosthesis creates the Prosthesis an excellent match between those responsible for durability Properties so that such a prosthesis can be used for the life of the patient given is.

The socket 11 and the dentures 24 and 25 are pressed using the pressing process produced by the short carbon fibers 27 in a heated to about 110 "C Form can be entered, whereupon the matrix material heated to approx. 125-C is poured, pressed and hardened.

The prosthesis shaft 13 as well as the bone replacement 20 and the bone plate 22, on the other hand, are produced in the winding process, in that the in the matrix material impregnated carbon fibers 26 are wound into a wound body, from the form-fitting Parts separated and shaped to form the corresponding parts or how in the case of the shaft, are glued together with the same matrix material. Here care is taken that the fibers 26 are parallel to the shaft surface in the longitudinal direction get lost.

The subsequent hardening process is carried out for all composite parts Heating by putting the prostheses 7 hours at 100 ° C, 2 hours at 130 ° C and then be held at 160 # C for another 16 hours.

In the hip joint prosthesis, the ceramic head 12 is free The end 16 of the shaft 13 is attached. An intermediate layer 17 made of an elastic Material, e.g.

Polyether urethane is used to dampen impact forces.

The intermediate layer 17 is when using a curable elastomer hardened directly on the shaft end 16, so that it forms a structural unit with the shaft 13 forms.

Claims (10)

P a t e n t a n sp r ü c h e Endoprosthesis made of carbon fiber reinforced Composite material, characterized in that the carbon fibers (6, 27) in one Matrix of polyphenol glycidyl ether and 4,4'-diaminodiphenyl sulfone are embedded. 2 endoprosthesis according to claim 1, characterized by the use for bone substitutes (20). 3. Endoprosthesis according to claim 1, characterized by the use for bone plates (22). 4. Endoprosthesis according to claim 1, characterized by the use for dentures (24, 25). 5. Endoprosthesis according to claim 12, characterized by the use for joint prostheses, at least one prosthesis part (11, 13) made of carbon The reinforced composite consists of a matrix of polyphenol glycidyl ether and 4,4 "-Diaraino-diphenyl sulfone contains. 6. Endoprosthesis according to claim 5, characterized in that the prosthesis part (11) made of carbon fiber reinforced composite material on a second prosthesis part (12) can be articulated, and that the second prosthesis part consists of at least one joint end Ceramic is made. 7. Endoprosthesis according to claim 6, characterized in that the second Protective part consisting of a joint head (12) made of ceramic and a prosthesis shaft (13) consists of carbon fiber reinforced composite material, the matrix of which is polyphenol glycidyl ether and 4,4'-diaminodiphenyl sulfone. 8. Endoprosthesis according to claim 7, characterized in that the joint head (12) using an elastic intermediate layer (17) on one end (16) of the Prosthesis shaft (13) is detachably attached. 9. Endoprosthesis according to claim 8, characterized in that the intermediate layer (17) consists of toluene diisocyanate and polytetramethylene ether glycol, which is 3.3 ' Dichloro-4,4'-diaminodiphenylmethane on the shaft end (16) are cured. 10. A method for producing a prosthesis according to claim 1, characterized characterized in that the endoprosthesis (11, 13, 20, 22, 24, 25) according to its shape is subjected to a hardening process in which the prosthesis is about 7 hours to about 100 ° C, then about 2 hours to about 130 "C and finally about 16 hours to about 1600C is held.