EP0577342A1
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EP
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Sintered hydroxyapatite compositions and method for the preparation thereof
Assignee: Queen Mary University of London
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Filing: 1993-06-24
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Granted: —
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Expires: 2013-06-24
Abstract
Abstract A sintered enhanced hydroxyapatite which comprises hydroxyapatite, Ca₁₀(P0₄)₆(OH)₂, and a biocompatible glass based upon Ca0 and P₂0₅. The enhanced hydroxyapatite of the present invention may be used as bone implants, as bone fillers, as coatings for artificial joints or in pharmaceutical compositions for use as bone cements or dental cements.
Inventors
- 👤 William Prof. Bonfield
- 👤 Garth Winton Prof. Hastings
- 👤 Jonathan Campbell Dr. Knowles
- 👤 Jose Domingos Da Silva Santos
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 10:18
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/447; A; A61; A61K; A61K6/00; A61K6/80; A61K6/831; A61K6/836; A61K6/838; A61L; A61L24/00; A61L24/02; A61L27/00; A61L27/02; A61L27/12; A61L27/28; A61L27/30; A61L27/32; A61F; A61F2/00; A61F2/02; A61F2/28; A61F2/30; A61F2/30767; A61F2/3094; A61F2002/30968; A61F2/46; A61F2002/4631; A61F2310/00; A61F2310/00005; A61F2310/00179; A61F2310/00293; A61F2310/00389; A61F2310/00592; A61F2310/00796; A61L2430/00; A61L2430/02
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
19 words
A sintered enhanced hydroxyapatite which comprises hydroxyapatite, Ca 1O (P0₄)₆(OH)₂, and a biocompatible glass based upon Ca0 and P₂0₅.
Claim 2
Dependent Claim
28 words
A material as claimed in claim 1 wherein the biocompatible glass is contained in an amount of less than 10% by weight based on the weight of hydroxyapatite.
Claim 3
Dependent Claim
29 words
A material as claimed in claim 2 wherein the biocompatible glass is contained in an amount of from 2.5% to 5.0% by weight based on the weight of hydroxy-apatite.
Claim 4
Dependent Claim
21 words
A material as claimed in any one of the preceding claims wherein the biocompatible glass is a two oxide Ca0-P₂0₅ glass.
Claim 5
Dependent Claim
18 words
A material as claimed in claim 4 wherein the glass comprises a mole ratio of Ca0:P₂0₅ of 50:50.
Claim 6
Dependent Claim
22 words
A material as claimed in any one of claims 1 to 3 wherein the biocompatible glass is a three oxide Ca0-P₂0₅-Na₂0 glass.
Claim 7
Dependent Claim
22 words
A material as claimed in any one of claims 1 to 3 wherein the biocompatible glass is a four oxide Ca0-P₂0₅-Na₂0-Al₂0₃ glass.
Claim 8
Dependent Claim
36 words
A method for the preparation of a material as claimed in claim 1 which comprises sintering a mixture of hydroxyapatite, Ca₁₀(P0₄)₆(OH)₂, and a biocompatible glass based upon Ca0 and P₂0₅ at a temperature of above 1200°C.
Claim 9
Dependent Claim
24 words
A method as claimed in claim 8 wherein the sintering is carried out at a temperature in the range of from 1250° to 1350°C.
Claim 10
Dependent Claim
26 words
A method as claimed in claim 8 or claim 9 wherein the mixture of hydroxyapatite and biocompatible glass has a particle of less than 75 micrometres.
Claim 11
Independent Claim
33 words
A method as claimed in any one of claims 8 to 10 wherein the biocompatible glass is contained in an amount of less than 10% by weight based on the weight of hydroxyapatite.
Claim 12
Dependent Claim
29 words
A method as claimed in claim 11 wherein the biocompatible glass is contained in an amount of from 2.5% to 5.0% by weight based on the weight of hydroxy-apatite.
Claim 13
Independent Claim
22 words
A method as claimed in any one of claims 8 to 12 wherein the biocompatible glass is a two oxide Ca0-P₂0₅ glass.
Claim 14
Dependent Claim
18 words
A method as claimed in claim 13 wherein the glass comprises a mole ratio of Ca0:P₂0₅ of 50:50.
Claim 15
Independent Claim
22 words
A method as claimed in any one of claims 8 to 12 wherein the biocompatible glass is a three oxide Ca0-P₂0₅-Na₂0 glass.
Claim 16
Independent Claim
22 words
A method as claimed in any one of claims 8 to 12 wherein the biocompatible glass is a four oxide Ca0-P₂0₅-Na₂0-Al₂0₃ glass.
Claim 17
Dependent Claim
21 words
A bone implant or bone filler which comprises an enhanced hydroxyapatite as claimed in any one of claims 1 to 7.
Claim 18
Dependent Claim
32 words
An artificial joint which comprises a coating of an enhanced hydroxyapatite as claimed in any one of claims 1 to 7 on at least a part of a metal or alloy joint.
Claim 19
Dependent Claim
25 words
A composition which comprises an enhanced hydroxyapatite as claimed in any one of claims 1 to 7 together with a pharmaceutically acceptable diluent or carrier.
Claim 20
Dependent Claim
16 words
A composition as claimed in claim 19 which is a bone cement or a dental cement.
References Cited (Backward Citations)
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