US5356436A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Materials for living hard tissue replacements
Assignee: TDK Corp
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Filing: 1992-04-21
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Granted: 1994-10-18
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Expires: 2012-04-21
Abstract
Abstract The materials for living hard tissue replacements of the present invention comprise a ceramic material which contain Cao and SiO 2 as essential components, and MgO as an optional components, are substantially free from calcium phosphate and are capable of forming a compound based on calcium phosphate by contact with an aqueous solution containing phosphorus, and show high biological affinity.
Inventors
- 👤 Tohru Nonami
- 👤 Hiroyasu Noma
- 👤 Shinya Nakajima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 09:20
CPC Classifications
A; A61; A61L; A61L27/00; A61L27/02; A61L27/10; C; C04; C04B; C04B35/00; C04B35/01; C04B35/16; C04B35/22; Y; Y10; Y10S; Y10S623/00; Y10S623/901
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
110 words
A method for replacement of living hard tissue comprising: providing an implant comprising a ceramic material which contains at least 40% by volume of a diopside composition, a wollastonite composition or a mixture of diopside and wollastonite compositions, and which (i) contains CaO and SiO 2 as essential components, (ii) is substantially free from calcium phosphate and (iii) is capable of forming a compound based in calcium phosphate by contact with an aqueous solution containing phosphorous, said CaO and SiO 2 being present in a weight ratio of CaO to SiO 2 of between 1:4 and 6:1; and inserting said implant into a living body to replace living hard tissue.
Claim 2
Independent Claim
110 words
A method for replacement of living hard tissue comprising: providing an implant comprising a ceramic material which contains at least 40% by volume of a diopside composition, a wollastonite composition or a mixture of diopside and wollastonite compositions, and which (i) contains CaO and SiO 2 as essential components, (ii) is substantially free from calcium phosphate and (iii) is capable of forming a compound based in calcium phosphate by contact with an aqueous solution containing phosphorous, said CaO and SiO 2 being present in a weight ratio of CaO to SiO 2 of between 1:4 and 6:1; and inserting said implant into a living body to replace living hard tissue.
Claim 3
Dependent Claim
25 words
The process as claimed in claim 1, wherein said ceramic material contains MgO in addition to the essential components of CaO and SiO 2 .
Claim 4
Dependent Claim
35 words
The process as claimed in claim 2, wherein said ceramic material contains 10 to 88% by weight of CaO, 10 to 80% by weight of SiO 2 and 2 to 35% by weight of MgO.
Claim 5
Dependent Claim
35 words
The process as claimed in claim 3, wherein said ceramic material contains 18 to 47% by weight of CaO, 37 to 68% by weight of SiO 2 and 10 to 25% by weight of MgO.
Claim 6
Dependent Claim
21 words
The process as claimed in claim 1, wherein said ceramic material contains at least 40% by volume of a diopside composition.
Claim 7
Dependent Claim
32 words
The process as claimed in claim 1, wherein said ceramic material contains at least 50% by volume of a diopside composition, a wollastonite composition or a mixture of diopside and wollastonite compositions.
Claim 8
Dependent Claim
32 words
The process as claimed in claim 6, wherein said ceramic material contains 70% to 100% by volume of a diopside composition, a wollastonite composition or a mixture of diopside and wollastonite compositions.
Claim 9
Dependent Claim
25 words
The process as claimed in claim 1, wherein said implant comprises a substrate having a coat layer of said ceramic material on a surface thereof.
Claim 10
Dependent Claim
19 words
The process as claimed in claim 8, wherein said coat layer has a thickness of 1 to 5000 gm.
Claim 11
Dependent Claim
19 words
The process as claimed in claim 1, wherein said coat layer has a thickness of 10 to 2000 μm.
Claim 12
Dependent Claim
19 words
The process as claimed in claim 10, wherein said coat layer has a thickness of 20 to 1000 μm.
Claim 13
Dependent Claim
20 words
The process as claimed in claim 8, wherein said coat layer has a surface roughness of 1 to 200 μm.
Claim 14
Dependent Claim
20 words
The process as claimed in claim 12, wherein said coat layer has a surface roughness of 5 to 100 μm.
Claim 15
Dependent Claim
13 words
The process as claimed in claim 8, wherein said coat layer is porous.
Claim 16
Dependent Claim
16 words
The process as claimed in claim 8, wherein said substrate comprises metal, ceramic, glass or plastic.
Claim 17
Dependent Claim
48 words
The process as claimed in claim 6, wherein said substrate comprises a metal selected from the group consisting of Ti, W, Ni-Cr alloy, Fe-Cr-Al alloy, Ti-Zr alloy, Fe-Ni-Cr alloy, Mo, Ti-Al-V alloy, Co-Cr-Mo alloy, Ti-Mo alloy, Co-Cr-Ni alloy, stainless steel 304, stainless steel 310 and stainless steel 316.
Claim 18
Dependent Claim
16 words
The process as claimed in claim 6, wherein said substrate comprises Ti or an alloy thereof.
Claim 19
Dependent Claim
28 words
The process as claimed in claim 6, wherein said substrate comprises a ceramic selected from the group consisting of alumina, zirconia, silicon carbide, tungsten nitride and silicon nitride.
Claim 20
Dependent Claim
34 words
The process as claimed in claim 1, wherein said implant is a porous body of said ceramic material having a pore diameter of 5 to 2000 μm and a porosity of 10 to 80%.
Claim 21
Dependent Claim
20 words
The process as claimed in claim 19, wherein said porous body has a pore diameter of 10 to 1000 μm.
Claim 22
Dependent Claim
18 words
The process as claimed in claim 19, wherein said porous body has a porosity of 20 to 70%.
Claim 23
Dependent Claim
18 words
The process as claimed in claim 21, wherein said porous body has a porosity of 25 to 60%.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1997-10-17 | 1998-04-18 | 1998-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-10-17 | 2002-04-18 | 2002-10-18 | $3760.00 | Window Closed / Lapsed |
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