US4230455A
Expired / Lapsed
US
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Prosthetic teeth and bones
Assignee: Pentax Corp
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Filing: 1978-12-04
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Granted: 1980-10-28
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Expires: 1998-12-04
Abstract
Abstract Prosthetic teeth and bones having superior affinity for the living body and having a compression strength of about 4×10 -3 kg/cm 2 or higher and a flexural strength of about 2.7×10 3 kg/cm 2 or higher, which comprise a composite material comprising (a) a sufficiently fine powder having an average particle size of about 2 μm or less comprising at least 50% by weight of Ca 10 (PO 4 ) 6 (OH) 2 and not more than about 50% by weight of at least one additive selected from the group consisting of Ca 3 (PO 4 ) 2 , AlPO 4 , Al 2 O 3 , AlF 3 , SiO 2 , Mg(PO 4 ) 2 , and the fluorides, chlorides and oxides of Li, Na, K, Mg and Ca, and (b) at least one fibrous material having the coefficient of thermal expansion nearly equal to or slightly lower than that of the hydroxy-apatite selected from the group consisting of fibers, fine filaments and metal whiskers, ceramics or glass, said fibrous material being present at least 50 μm inside the surface of the prosthetic teeth and bones, and said composite material being cold compression-molded and then sintered.
Inventors
- 👤 Tsuneo Hidaka
- 👤 Masahide Inoue
- 👤 Masatomi Ebihara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:19
CPC Classifications
A; A61; A61C; A61C8/00; A61C8/0012; A61F; A61F2/00; A61F2/02; A61F2/28; A61F2/30; A61F2/3094; A61F2/30965; A61L; A61L27/00; A61L27/40; A61L27/42; A61L27/425; A61L27/44; A61L27/46; C; C04; C04B; C04B35/00; C04B35/01; C04B35/447; A61F2002/30001; A61F2002/30003; A61F2002/30004; A61F2002/30009; A61F2/30767; A61F2/30907; A61F2002/30909; A61F2250/00; A61F2250/0014; A61F2250/0028; A61F2310/00; A61F2310/00005; A61F2310/00179; A61F2310/00293; A61L2430/00; A61L2430/02
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
215 words
Prosthetic teeth and bones having superior affinity for the living body and having a compression strength of about 4×10 3 kg/cm 2 or higher and a flexural strength of about 2.7×10 3 kg/cm 2 or higher, which comprise a composite material comprising (a) a sufficiently fine powder having an average particle size of about 2 μm or less comprising at least 50% by weight of Ca 10 (PO) 4 ) 6 (OH) 2 and not more than about 50% by weight of at least one additive selected from the group consisting of Ca 3 (PO 4 ) 2 , AlPO 4 , Al 2 O 3 , AlF 3 , SiO 2 , Mg(PO 4 ) 2 , and the fluorides, chlorides and oxides of Li, Na, K, Mg and Ca, and (b) at least one fibrous material having the coefficient of thermal expansion nearly equal to or slightly lower than that of the hydroxy-apatite selected from the group consisting of fibers, fine filaments and metal whiskers, ceramics or glass, said fibrous material being present at least 50 μm inside the surface of the prosthetic teeth and bones, and said composite material being a laminate of said fibrous material interposed between two layers of said fine powder and having been cold compression-molded and then sintered.
Claim 2
Dependent Claim
215 words
Prosthetic teeth and bones having superior affinity for the living body and having a compression strength of about 4×10 3 kg/cm 2 or higher and a flexural strength of about 2.7×10 3 kg/cm 2 or higher, which comprise a composite material comprising (a) a sufficiently fine powder having an average particle size of about 2 μm or less comprising at least 50% by weight of Ca 10 (PO) 4 ) 6 (OH) 2 and not more than about 50% by weight of at least one additive selected from the group consisting of Ca 3 (PO 4 ) 2 , AlPO 4 , Al 2 O 3 , AlF 3 , SiO 2 , Mg(PO 4 ) 2 , and the fluorides, chlorides and oxides of Li, Na, K, Mg and Ca, and (b) at least one fibrous material having the coefficient of thermal expansion nearly equal to or slightly lower than that of the hydroxy-apatite selected from the group consisting of fibers, fine filaments and metal whiskers, ceramics or glass, said fibrous material being present at least 50 μm inside the surface of the prosthetic teeth and bones, and said composite material being a laminate of said fibrous material interposed between two layers of said fine powder and having been cold compression-molded and then sintered.
Claim 3
Dependent Claim
51 words
The prosthetic teeth and bones of claim 1, wherein the amount of the weight proportion of Ca 10 (PO 4 ) 6 (OH) 2 to said additive is about 50 to 99.9% by weight of Ca 10 (PO 4 ) 6 (OH) 2 to about 0.1 to about 50% by weight.
Claim 4
Dependent Claim
18 words
The prosthetic teeth and bones of claim 1, wherein the fibrous material is arranged both lengthwise and crosswise.
Claim 5
Dependent Claim
19 words
The prosthetic teeth and bones of claim 3, wherein the fibrous material is in the form of a fabric.
Claim 6
Dependent Claim
20 words
The prosthetic teeth and bones of claim 4, wherein the fibrous material is in the form of a woven fabric.
Claim 7
Dependent Claim
20 words
The prosthetic teeth and bones of claim 4, wherein the fibrous material is in the form of a knitted fabric.
Claim 8
Dependent Claim
18 words
The prosthetic teeth and bones of claim 4, wherein the fibrous material is woven silicate glass fiber fabric.
Claim 9
Dependent Claim
31 words
The prosthetic teeth and bones of claim 1, wherein the sintering is performed at a temperature of about 800° to about 1500° C. for about 15 minutes to about 40 hours.
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) | 1983-10-28 | 1984-04-28 | 1984-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-28 | 1988-04-28 | 1988-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-28 | 1992-04-28 | 1992-10-28 | $7700.00 | Window Closed / Lapsed |