Patent US4940637A successfully refreshed from Google Patents.
US4940637A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dental foil and crown
Assignee: Individual
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Filing: 1986-12-31
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Granted: 1990-07-10
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Expires: 2006-12-31
Abstract
Abstract A dental crown restoration which comprises a metal coping and a relatively thick outer coating of a ceramic dental veneer. The metal coping is composed of a lamination of a low fusing temperature precious metal component substantially or entirely of gold and a high-fusing temperature precious metal component. The high fusing component is formed from three layers with one layer composed of from 90 to 100% palladium bounded on both sides by a gold based layer.
Inventors
- 👤 Itzhak Shoher
- 👤 Aharon Whiteman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:32
CPC Classifications
A; A61; A61C; A61C13/00; A61C13/0003; A61C5/00; A61C5/70; A61C5/77; A61K; A61K6/00; A61K6/80; A61K6/84; A61K6/844; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12431; Y10T428/12438; Y10T428/12493; Y10T428/12771; Y10T428/12861; Y10T428/12868; Y10T428/12875; Y10T428/12889
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
90 words
A metal foil for forming a dental coping in the construction of a dental restoration in which said dental coping has a veneering composition applied thereon following heat treatment of such coping, with said metal foil having one or more layers of a high fusing temperature precious metal consisting essentially of a gold and palladium based composition having a high fusing temperature above the temperature of said heat treatment, and having a low fusing temperature layer of gold or gold alloy on each side of said high fusing temperature layer.
Claim 2
Dependent Claim
90 words
A metal foil for forming a dental coping in the construction of a dental restoration in which said dental coping has a veneering composition applied thereon following heat treatment of such coping, with said metal foil having one or more layers of a high fusing temperature precious metal consisting essentially of a gold and palladium based composition having a high fusing temperature above the temperature of said heat treatment, and having a low fusing temperature layer of gold or gold alloy on each side of said high fusing temperature layer.
Claim 3
Dependent Claim
32 words
A metal foil as defined in claim 1 wherein said high fusing temperature metal further comprises one or more of the following elements: iridium, rhenium, ruthenium, silver copper, platinum and alloys thereof.
Claim 4
Dependent Claim
25 words
A metal foil as defined in claim 2 in which said high fusing temperature metal layer has a thickness of between 25 and 50 microns.
Claim 5
Dependent Claim
81 words
A dental crown comprising a metal coping formed from a heat treated metal foil composed of one or more high fusing temperature precious metal layer(s) consisting essentially of a palladium and gold based composition and a low fusing temperature layer of gold or gold alloy on each side thereof, with said heat treatment being sufficient to melt said low fusing temperature layer and a dental veneer composed of a ceramic or polymeric based composition covering part or all of the coping.
Claim 6
Dependent Claim
81 words
A dental crown comprising a metal coping formed from a heat treated metal foil composed of one or more high fusing temperature precious metal layer(s) consisting essentially of a palladium and gold based composition and a low fusing temperature layer of gold or gold alloy on each side thereof, with said heat treatment being sufficient to melt said low fusing temperature layer and a dental veneer composed of a ceramic or polymeric based composition covering part or all of the coping.
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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) | 1993-07-09 | 1994-01-08 | 1994-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-09 | 1998-01-08 | 1998-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-09 | 2002-01-08 | 2002-07-10 | $7700.00 | Window Closed / Lapsed |