US4708652A
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Apatite composite ceramics
Assignee: Nikon Corp
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Filing: 1985-12-19
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Granted: 1987-11-24
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Expires: 2005-12-19
Abstract
Abstract This invention provides a novel apatite composite ceramic useful for implants such as artificial dental root, artificial bone or the like. The apatite composite ceramic comprises an interconnected structure of fluorapatite phase and an at least partially crystallized biologically active glass phase, which ceramic is obtained by reaction-sintering at a sintering temperature of 700 DEG -1100 DEG C. at a pressure of at least atmospheric pressure a powder mixture of a synthetic hydroxyapatite (A) and a biologically active glass (B) containing fluoride ions and having a crystallization temperature below the sintering temperature in a weight ratio of A/B ranging from 60/40 to 30/70. The reaction-sintered material has excellent biological affinity and high mechanical strength.
Inventors
- 👤 Takamitsu Fujiu
- 👤 Masaaki Mochida
- 👤 Makoto Ogino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:18
CPC Classifications
A; A61; A61C; A61C13/00; A61C13/08; A61C8/00; A61C8/0012; A61F; A61F2/00; A61F2/02; A61F2/28; A61K; A61K6/00; A61K6/50; A61K6/58; A61K6/80; A61K6/802; A61K6/807; A61K6/816; A61K6/818; A61K6/822; A61K6/824; A61K6/831; A61K6/833; A61K6/838; A61L; A61L27/00; A61L27/02; A61L27/10; A61L27/12; C; C03; C03C; C03C10/00; C03C10/16; C04; C04B; C04B35/00; C04B35/01; C04B35/447; A61F2310/00; A61F2310/00005; A61F2310/00179; A61F2310/00293; Y; Y10; Y10S; Y10S623/00; Y10S623/924
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
90 words
An apatite composite ceramic comprising a fluorapatite phase and an at least partially crystallized biologically active glass phase, which ceramic is obtained by reaction-sintering at a sintering temperature of 900°-1100° C. at a pressure of at least atmospheric pressure a powder mixture of a synthetic hydroxyapatite (A) and a biologically active glass (B) which contains fluoride ions corresponding to F 2 of 5-20 mol% based on the glass (B) and which has a crystallization temperature below said sintering temperature, in a weight ratio of A/B ranging from 60/40 to 30/70.
Claim 2
Dependent Claim
90 words
An apatite composite ceramic comprising a fluorapatite phase and an at least partially crystallized biologically active glass phase, which ceramic is obtained by reaction-sintering at a sintering temperature of 900°-1100° C. at a pressure of at least atmospheric pressure a powder mixture of a synthetic hydroxyapatite (A) and a biologically active glass (B) which contains fluoride ions corresponding to F 2 of 5-20 mol% based on the glass (B) and which has a crystallization temperature below said sintering temperature, in a weight ratio of A/B ranging from 60/40 to 30/70.
Claim 3
Dependent Claim
14 words
An implant formed of the apatite composite ceramics as set forth in claim 1.
Claim 4
Dependent Claim
13 words
An implant according to claim 2, wherein said implant is a dental implant.
Claim 5
Dependent Claim
154 words
An apatite composite ceramic comprising a fluorapatite phase and an at least partially crystallized biologically active glass phase, which ceramic is obtained by reaction-sintering at a sintering temperature of 900°-1100° C. at a pressure of at least atmospheric pressure a powder mixture of a synthetic hydroxyapatite (A) and a biologically active glass (B) selected from the scope of the following composition: ______________________________________
SiO.sub.2 35-60 mol %
B.sub.2 O.sub.3 0-15 mol %
Na.sub.2 O 10-30 mol %
CaO 5-40 mol %
TiO.sub.2 0-10 mol %
P.sub.2 O.sub.5 0-15 mol %
K.sub.2 O 0-20 mol %
Li.sub.2 O 0-10 mol %
MgO 0- 5 mol %
Al.sub.2 O.sub.3 + ZrO.sub.2 + Nb.sub.2 O.sub.5
0- 8 mol %
La.sub.2 O.sub.3 + Ta.sub.2 O.sub.5 + Y.sub.2 O.sub.3
0- 8 mol %
F.sub.2 5-20 mol %
______________________________________ said biologically active glass having a crystallization temperature below said sintering temperature, the weight ratio of A/B ranging from 60/40 to 30/70.
Claim 6
Dependent Claim
154 words
An apatite composite ceramic comprising a fluorapatite phase and an at least partially crystallized biologically active glass phase, which ceramic is obtained by reaction-sintering at a sintering temperature of 900°-1100° C. at a pressure of at least atmospheric pressure a powder mixture of a synthetic hydroxyapatite (A) and a biologically active glass (B) selected from the scope of the following composition: ______________________________________
SiO.sub.2 35-60 mol %
B.sub.2 O.sub.3 0-15 mol %
Na.sub.2 O 10-30 mol %
CaO 5-40 mol %
TiO.sub.2 0-10 mol %
P.sub.2 O.sub.5 0-15 mol %
K.sub.2 O 0-20 mol %
Li.sub.2 O 0-10 mol %
MgO 0- 5 mol %
Al.sub.2 O.sub.3 + ZrO.sub.2 + Nb.sub.2 O.sub.5
0- 8 mol %
La.sub.2 O.sub.3 + Ta.sub.2 O.sub.5 + Y.sub.2 O.sub.3
0- 8 mol %
F.sub.2 5-20 mol %
______________________________________ said biologically active glass having a crystallization temperature below said sintering temperature, the weight ratio of A/B ranging from 60/40 to 30/70.
Claim 7
Dependent Claim
91 words
A process for preparing an apatite composite ceramic having a fluorapatite phase and an at least partially crystallized biologically active glass phase, comprising: reaction-sintering at a sintering temperature of 900°-1100° C. and at a pressure of at least atmospheric pressure a powder mixture of a synthetic hydroxyapatite (A) and a biologically active glass (B) which contains fluoride ions corresponding to F 2 of 5-20 mol% based on the glass (B) and which has a crystallization temperature below said sintering temperature, in a weight ratio of A/B ranging from 60/40 to 30/70.
Claim 8
Dependent Claim
91 words
A process for preparing an apatite composite ceramic having a fluorapatite phase and an at least partially crystallized biologically active glass phase, comprising: reaction-sintering at a sintering temperature of 900°-1100° C. and at a pressure of at least atmospheric pressure a powder mixture of a synthetic hydroxyapatite (A) and a biologically active glass (B) which contains fluoride ions corresponding to F 2 of 5-20 mol% based on the glass (B) and which has a crystallization temperature below said sintering temperature, in a weight ratio of A/B ranging from 60/40 to 30/70.
Claim 9
Dependent Claim
14 words
A process as set forth in claim 5, including hot-press sintering of said mixture.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-11-23 | 1991-05-25 | 1991-11-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-23 | 1995-05-25 | 1995-11-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-23 | 1999-05-25 | 1999-11-24 | $7700.00 | Window Closed / Lapsed |