US4295941A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing a metal ceramic dental restoration
Assignee: HEALTHCO Inc A CORP OF MASS
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Filing: 1979-12-07
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Granted: 1981-10-20
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Expires: 1999-12-07
Abstract
Abstract The method of the present invention involves fabricating a cast metal framework from a non-precious metal alloy containing nickel, electroplating a thin film of gold over a predetermined surface area of the framework, distributing finely divided gold particles of varying size about the electroplated surface and firing successive layers of porcelain over the predetermined surface area.
Inventors
- 👤 Stewart J. Lustgarten
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:51
CPC Classifications
A; A61; A61C; A61C13/00; A61C13/0003; A61C13/0006; A61C13/001; A61C5/00; A61C5/70; A61C5/77; A61K; A61K6/00; A61K6/80; A61K6/84; A61K6/844
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
140 words
A method of manufacturing a fixed prosthodontic metal ceramic dental restoration comprising casting a metal framework from a metal composition comprising an alloy of nickel and chromium having at least 4% nickel, electroplating a thin film deposit of gold between about 0.4 to 1 mil in thickness over a predetermined surface area of said framework with said gold deposit being in intimate contact with the nickel chromium alloy; distributing finely divided particles containing a major proportion of gold which vary in size between 1 to no more than about 20 microns over said electroplated gold surface and firing successive layers of porcelain over said predetermined surface area in a firing temperature range of between about 1600° F. to 1900° F. whereby the firing of said porcelain layers simultaneously causes said finely divided particles to form beads of substantially globular shape.
Claim 2
Independent Claim
140 words
A method of manufacturing a fixed prosthodontic metal ceramic dental restoration comprising casting a metal framework from a metal composition comprising an alloy of nickel and chromium having at least 4% nickel, electroplating a thin film deposit of gold between about 0.4 to 1 mil in thickness over a predetermined surface area of said framework with said gold deposit being in intimate contact with the nickel chromium alloy; distributing finely divided particles containing a major proportion of gold which vary in size between 1 to no more than about 20 microns over said electroplated gold surface and firing successive layers of porcelain over said predetermined surface area in a firing temperature range of between about 1600° F. to 1900° F. whereby the firing of said porcelain layers simultaneously causes said finely divided particles to form beads of substantially globular shape.
Claim 3
Dependent Claim
14 words
A method as defined in claim 1 wherein said nickel is at least 20%.
Claim 4
Dependent Claim
27 words
A method as defined in claim 2 wherein said finely divided particles are suspended in a carrier adapted to volatilize within the firing range of said porcelain.
Claim 5
Dependent Claim
38 words
A method as defined in claim 3 wherein said finely divided particles containing gold comprises an alloy substantially of gold with a minor concentration of elements selected from the class consisting of B, Al, Mg, Cu and Si.
Claim 6
Dependent Claim
32 words
A method as defined in claim 4 wherein said framework comprises the following composition by weight: 20-25% Cr; 1.7% Be; about 70-75% Ni with trace elements of Fe, Si, C and B.
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) | 1984-10-19 | 1985-04-20 | 1985-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-19 | 1989-04-20 | 1989-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-19 | 1993-04-20 | 1993-10-20 | $7700.00 | Window Closed / Lapsed |