Patent US5080589A successfully refreshed from Google Patents.
US5080589A
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US
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Artificial tooth crowns
Assignee: Sandvik AB
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Filing: 1989-12-20
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Granted: 1992-01-14
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Expires: 2009-12-20
Abstract
Abstract The present invention relates to an artificial tooth crown composed of a prefabricated coping designed for artificial strength densely sintered ceramic material with powder metallurgical methods. The tooth crown is given the final shape by a veneer material attached to the external surface of the coping by e.g., firing or dental porcelain. The tooth crown can be made in less manufacturing time with an increase in the strength and the accuracy to shape.
Inventors
- 👤 Agneta E. Oden
- 👤 Hans T. Rostvall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 08:38
CPC Classifications
A; A61; A61C; A61C13/00; A61C13/0003; A61C5/00; A61C5/20; A61C5/70; A61C5/77; A61K; A61K6/00; A61K6/15; A61K6/17; A61K6/20; A61K6/70; A61K6/71; A61K6/78; A61K6/80; A61K6/802; A61K6/807; A61K6/816; A61K6/818; A61K6/822; A61K6/831; A61K6/836
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
46 words
Artificial tooth crown comprising a coping and a veneer wherein the coping is prefabricated of a sintered biocompatible ceramic material which shrinks during sintering, has a sintered relative density of >98% and wherein the ceramic material comprises >50% by weight of Al 2 O 3 .
Claim 2
Dependent Claim
46 words
Artificial tooth crown comprising a coping and a veneer wherein the coping is prefabricated of a sintered biocompatible ceramic material which shrinks during sintering, has a sintered relative density of >98% and wherein the ceramic material comprises >50% by weight of Al 2 O 3 .
Claim 3
Dependent Claim
18 words
The artificial tooth crown of claim 1 wherein the biocompatible ceramic material has a relative density of >99.5%.
Claim 4
Dependent Claim
46 words
The artificial tooth crown according to claim 1 wherein the ceramic material also includes one or more oxides of the group consisting of TiO 2 , MgO, ZrO 2 or ZrO 2 stabilized with up to 10 mol % Y 2 O 3 , or CaO.
Claim 5
Dependent Claim
21 words
The artificial tooth crown of claim 1 wherein the Al 2 O 3 is present in an amount >85% by weight.
Claim 6
Dependent Claim
23 words
The artificial tooth crown according to claim 1 wherein the coping also comprises whiskers and/or particles of SiC, TiN, ZrO 2 and/or ZrN.
Claim 7
Dependent Claim
21 words
The artificial tooth crown according to claim 5 wherein ZrO 2 is present in an amount of from 3-12 weight %.
Claim 8
Dependent Claim
23 words
The artificial tooth crown according to claim 5 wherein SiC single crystal whiskers are present in an amount of from 10-30 weight %.
Claim 9
Dependent Claim
27 words
The artificial tooth crown according to claim 1 wherein the coping is coated with a layer of from 1-10 μm of Al 2 O 3 or TiN.
Claim 10
Dependent Claim
20 words
The artificial tooth crown according to claim 1 wherein the coping contains from 0.1-10 weight % of TiN and/or ZrN.
Claim 11
Dependent Claim
20 words
The artificial tooth crown according to claim 9 wherein the coping contains from 0.5-5 weight % of TiN and/or ZrN.
Claim 12
Dependent Claim
38 words
The artificial tooth crown according to claim 1 wherein the ceramic material comprises at least 50 weight % Al 2 O 3 , <25 weight % ZrO 2 and from 5-40 weight % of SiC single crystal whiskers.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-01-13 | 1995-07-15 | 1996-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-01-13 | 1999-07-15 | 2000-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-01-13 | 2003-07-15 | 2004-01-14 | $7700.00 | Window Closed / Lapsed |