Patent US4453977A successfully refreshed from Google Patents.
US4453977A
Expired / Lapsed
US
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Low silver containing dental amalgam alloys
Assignee: Manufacturers Hanover Trust Co
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Filing: 1982-06-15
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Granted: 1984-06-12
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Expires: 2002-06-15
Abstract
Abstract Conventional or non-conventional dental amalgam alloys in the form of lathe-cut, spherical shaped or irregular shaped particles of silver, tin, copper and zinc are improved by adding to the alloys at least one compound selected from Cu 6 Sn 5 , Cu 3 Sn or a mixture thereof. The resulting dental alloy mixture is low in silver, is corrosion resistant, and is used as a filling for dental cavities after amalgamation with mercury.
Inventors
- 👤 Charles F. Burns
- 👤 Edward J. Pilcicki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:27
CPC Classifications
A; A61; A61K; A61K6/00; A61K6/80; A61K6/84; A61K6/847; Y; Y10; Y10S; Y10S75/00; Y10S75/955
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
137 words
In a dental amalgamable composition comprising about 50 to 95% by weight of at least one amalgamable alloy of 40 to 75% by weight of silver, 20 to 30% by weight of tin, 2 to 30% by weight of copper, and 0.5 to 30% by weight of at least one member selected from the group consisting of indium, zinc, gold, mercury, manganese, cadmium, and aluminum, the improvement comprising adding to this composition from about 5 to about 50% by weight of at least one member selected from the group consisting of Cu 6 Sn 5 , Cu 3 Sn, and a mixture thereof wherein the member is in the form of lathe-cut, spherical shaped, or irregular shaped particles and is composed of 30 to 70% by weight of copper and 70 to 30% by weight of tin.
Claim 2
Dependent Claim
137 words
In a dental amalgamable composition comprising about 50 to 95% by weight of at least one amalgamable alloy of 40 to 75% by weight of silver, 20 to 30% by weight of tin, 2 to 30% by weight of copper, and 0.5 to 30% by weight of at least one member selected from the group consisting of indium, zinc, gold, mercury, manganese, cadmium, and aluminum, the improvement comprising adding to this composition from about 5 to about 50% by weight of at least one member selected from the group consisting of Cu 6 Sn 5 , Cu 3 Sn, and a mixture thereof wherein the member is in the form of lathe-cut, spherical shaped, or irregular shaped particles and is composed of 30 to 70% by weight of copper and 70 to 30% by weight of tin.
Claim 3
Dependent Claim
17 words
The composition of claim 1 wherein 50% of Cu 6 Sn 5 is added to the composition.
Claim 4
Dependent Claim
16 words
The composition of claim 1 wherein 50% of Cu 3 Sn is added to the composition.
References Cited (Backward Citations)
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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) | 1987-06-12 | 1987-12-12 | 1988-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-06-12 | 1991-12-12 | 1992-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-06-12 | 1995-12-12 | 1996-06-12 | $7700.00 | Window Closed / Lapsed |