US5306302A
Expired / Lapsed
US
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Implant material
Assignee: Merck Patent GmbH
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Filing: 1991-09-09
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Granted: 1994-04-26
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Expires: 2011-09-09
Abstract
Abstract The invention relates to an implant material based on natural bone, which material is a sintered ceramic material in which the porous fine structure of the bone is present in essentially unchanged form and which comprises more than 99% of hydroxyapatite.
Inventors
- 👤 Hans J. Bauer
- 👤 Bianca Katzenmeier
- 👤 Matthias Kuntz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:18
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/36; A61L27/3683; A61L27/3687; A61L27/02; A61L27/12; A61L27/3604; A61L27/3608; A61L27/50; A61L27/56; A61F; A61F2310/00; A61F2310/00005; A61F2310/00179; A61F2310/00293; A61L2430/00; A61L2430/40
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
104 words
A process for production of an implant material based on natural bone, said implant material comprising a sintered ceramic material having a porous fine structure characteristic of natural bone in essentially unchanged form, and wherein more than 99% of said ceramic material is hydroxyapatite detectable by X-ray, said process comprising (a) subjecting bone material freed from all organic constituents to treatment with an aqueous solution of an organic acid selected from aliphatic C 1-5 -monocarboxylic acid and malonic acid, tartronic acid, succinic acid, malic acid, tartaric acid and citric acid, and (b) sintering the bone material at temperatures between 900° and 1400° C. thereafter.
Claim 2
Dependent Claim
104 words
A process for production of an implant material based on natural bone, said implant material comprising a sintered ceramic material having a porous fine structure characteristic of natural bone in essentially unchanged form, and wherein more than 99% of said ceramic material is hydroxyapatite detectable by X-ray, said process comprising (a) subjecting bone material freed from all organic constituents to treatment with an aqueous solution of an organic acid selected from aliphatic C 1-5 -monocarboxylic acid and malonic acid, tartronic acid, succinic acid, malic acid, tartaric acid and citric acid, and (b) sintering the bone material at temperatures between 900° and 1400° C. thereafter.
Claim 3
Dependent Claim
28 words
A process according to claim 1, wherein the acid treatment is carried out using an aqueous solution which contains 1 to 30% by weight of the organic acid.
Claim 4
Dependent Claim
28 words
A process according to claim 1, wherein the acid treatment is carried out using an aqueous solution which contains 5 to 10% by weight of the organic acid.
Claim 5
Dependent Claim
31 words
A process according to claim 1, wherein the acid treatment is carried out for a period of 2 minutes to 24 hours at a temperature between 20° C. and boiling temperature.
Claim 6
Dependent Claim
20 words
A process according to claim 1, wherein the acid treatment is carried out using an aqueous solution of citric acid.
Claim 7
Dependent Claim
21 words
A process according to claim 1, wherein the acid treatment is carried out using a recirculated aqueous solution of citric acid.
Claim 8
Dependent Claim
25 words
A process according to claim 1, further comprising subjecting the bone material to presintering at temperatures between 600° and 1000° C. before the acid treatment.
Claim 9
Dependent Claim
20 words
A process according to claim 1, wherein bone is freed of all organic constituents by chemical solution and extraction treatment.
Claim 10
Dependent Claim
33 words
A process according to claim 8, wherein bone is freed of all organic constituents selected from boiling and/or treatment with fat or protein dissolving solvents and/or treatment with H 2 O 2 .
Claim 11
Dependent Claim
18 words
A process according to claim 12, wherein said pyrolytic treatment is conducted at a temperature of 500°-1000° C.
Claim 12
Dependent Claim
18 words
A process according to claim 12, wherein said pyrolytic treatment is conducted at a temperature of 600°-800° C.
Claim 13
Dependent Claim
17 words
A process according to claim 1, wherein bone is freed of all organic constituents by pyrolytic treatment.
Claim 14
Dependent Claim
11 words
A process according to claim 1, wherein the bone is cancellous.
Claim 15
Dependent Claim
113 words
A process for production of an implant material based on natural bone, said implant material comprising a sintered ceramic material having a porous fine structure characteristic of natural bone in essentially unchanged form, and wherein more than 99% of said ceramic material is hydroxyapatite by X-ray, said process comprising (a) pyrolyzing bone material between 500° and 1000° C., (b) subjecting the bone material freed from all organic constituents to treatment with an aqueous solution of an organic acid selected from aliphatic C 1-5 -monocarboxylic acid and malonic acid, tartronic acid, succinic acid, malic acid, tartaric acid and citric acid, and (c) sintering the bone material at temperatures between 900° and 1400° C. thereafter.
Claim 16
Dependent Claim
113 words
A process for production of an implant material based on natural bone, said implant material comprising a sintered ceramic material having a porous fine structure characteristic of natural bone in essentially unchanged form, and wherein more than 99% of said ceramic material is hydroxyapatite by X-ray, said process comprising (a) pyrolyzing bone material between 500° and 1000° C., (b) subjecting the bone material freed from all organic constituents to treatment with an aqueous solution of an organic acid selected from aliphatic C 1-5 -monocarboxylic acid and malonic acid, tartronic acid, succinic acid, malic acid, tartaric acid and citric acid, and (c) sintering the bone material at temperatures between 900° and 1400° C. thereafter.
Claim 17
Dependent Claim
11 words
A process according to claim 14, wherein the bone is cancellous.
Claim 18
Dependent Claim
45 words
A sintered ceramic implant material based on natural bone having a porous fine structure characteristic of natural bone comprising: more than 99% of hydroxyapatite, said hydroxyapatite detectable by X-ray, wherein said porous fine structure is present in the ceramic implant material in essentially unchanged form.
Claim 19
Dependent Claim
45 words
A sintered ceramic implant material based on natural bone having a porous fine structure characteristic of natural bone comprising: more than 99% of hydroxyapatite, said hydroxyapatite detectable by X-ray, wherein said porous fine structure is present in the ceramic implant material in essentially unchanged form.
Claim 20
Dependent Claim
12 words
An implant material according to claim 16, wherein said bone is cancellous.
Claim 21
Dependent Claim
17 words
An implant material according to claim 16, wherein said ceramic material contains no amounts of calcium oxide.
References Cited (Backward Citations)
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