Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Processes of preparing a desired or intentional composition...
Patent
1997-05-14
1999-11-09
Merriam, Andrew E. C.
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Processes of preparing a desired or intentional composition...
523114, 523115, 524414, 524494, 525450, 528502C, 264320, 264325, 2643281, A61L 2700, B29C 4316, C08L 6700
Patent
active
059816198
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
This invention relates to most ideal biomaterials which can be substituted with the living body and are also useful in such applications as novel and effective artificial bones, artificial joints, artificial tooth roots, bone fillers, materials for osteosynthesis, bone prosthetic and the like that have bioactivities including the binding ability to the living body and inductivity of tissues, more particularly to a material for osteosynthesis having excellent physical strength, which comprises a crystalline thermoplastic polymer material that is degradable and absorbable in the living body, to an implant material comprising a composite material comprising the just described polymer material and bioceramics having bioactivities and to production processes thereof.
BACKGROUND ART
An implant could be regarded as one of ideal biomaterials, if it could be prepared from a material which is safe with no toxicity and can be present in the living body for a while by performing its mechanical and physiological functions and objects during the healing period, but is gradually degraded and disintegrated thereafter to be absorbed in the living body and excreted therefrom via the metabolic pathway in the living body, so that the region where it was implanted could finally be replaced by the living body to reconstruct original conditions of the living body.
In recent years, artificial bones, artificial joints, artificial tooth roots, bone fillers and bone prosthetic as substitutes for biological bones and cartilages which are hard tissues, and materials for osteosynthesis for the purpose of fixing fractured cartilages or hard bones in respective regions have been produced making use of various metals, ceramics and polymers.
In the field of surgery such as orthopedic surgery, plastic surgery, thoracic surgery, oral surgery, brain surgery and the like, plates, screws, pins and the like made of metals or ceramics are used as materials for osteosynthesis with the aim of fixing and binding biological bones.
However, being excessively high in mechanical strength and elastic modulus in comparison with biological bones, the materials for osteosynthesis made of metals have problems of, for example, causing a phenomenon of reduced strength of peripheral bones due to stress protection after the treatment. Also, the materials for osteosynthesis made of ceramics have excellent hardness and rigidity but are brittle, so that they have a fatal defect that it is apt to be broken. With regard to polymers, attempts are being made to improve their strengths which are generally lower than those of bones.
On the other hand, bioactive bioceramics which can be bound directly to bones have been used in many cases by directly implanting into or contacting with the human body, for the purpose of recovering or improving biological functions.
Also, certain bioceramics which bind directly and strongly to the living body and are gradually replaced by the living body have been studied continuously because of their unknown possibilities.
However, though their rigidity and hardness are generally large, the use of bioceramics as implants has a limitation because of their brittle properties of being easily chipped or broken by the momentary impact force in comparison with the case of metals, so that development of a material which has toughness but with no brittleness has been required in this field.
On the other hand, several cases have been known about polymers which are used as implants into peripheral areas of hard tissues, such as a silicone resin to be used as a substitute for cartilages, a hardenable acrylic resin as dental cement and braided cords made of polyester or polypropylene fibers for use in ligaments.
However, inert and high strength ultra-high molecular weight polyethylene, polypropylene, polytetrafluoroethylene and the other polymers to be used as substitutes for hard tissues in the living body are significantly lack in strength as substitutes for biological bones when used as such. Accordingly, when they are used alon
REFERENCES:
patent: 4968317 (1990-11-01), Tormala et al.
patent: 5702656 (1997-12-01), Sarver et al.
Okuno Masaki
Shikinami Yasuo
Merriam Andrew E. C.
Takiron Co., Ltd.
LandOfFree
Material for osteosynthesis and composite implant material, and does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Material for osteosynthesis and composite implant material, and , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Material for osteosynthesis and composite implant material, and will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1456958