Patent US5321447A successfully refreshed from Google Patents.
US4162172A
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Method of removing dental cement from surfaces
Assignee: DHP Corp
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Filing: 1978-02-06
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Granted: 1979-07-24
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Expires: 1998-02-06
Abstract
Abstract Carboxylate and zinc oxyphosphate types of dental cement are removed from dental products by applying a solution containing an organic acid having a COOH radical to the dental product. A preferred organic acid is citric acid.
Inventors
- 👤 James J. Longo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:46
CPC Classifications
C; C11; C11D; C11D7/00; C11D7/22; C11D7/26; C11D7/265; C11D7/261
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
63 words
In a method of removing a hardened zinc oxyphosphate dental cement from a surface, the improvement comprising forming a substantially aqueous or alcoholic solution of citric acid having a concentration of at least 1 gm citric acid per 10 ml of solution, and applying for at least about 3 minutes an amount of said solution to said surface effective to remove said cement.
Claim 2
Dependent Claim
63 words
In a method of removing a hardened zinc oxyphosphate dental cement from a surface, the improvement comprising forming a substantially aqueous or alcoholic solution of citric acid having a concentration of at least 1 gm citric acid per 10 ml of solution, and applying for at least about 3 minutes an amount of said solution to said surface effective to remove said cement.
Claim 3
Dependent Claim
52 words
In the method of claim 1 wherein the surface is on a dental product, placing the solution in an ultrasonic cleaner, and immersing the zinc oxyphosphate cement containing dental product in the citric acid solution, and utilizing mechanical agitation from the ultrasonic cleaner to enhance the removal of the zinc oxyphosphate cement.
Claim 4
Dependent Claim
27 words
In the method of claim 1 wherein the citric acid solution has a concentration no more than about 1 gram citric acid per 1.125 ml of water.
Claim 5
Dependent Claim
29 words
In the method of claim 2 wherein the dental product is made from a brightenable material, and utilizing the citric acid as a brightening agent for the dental product.
Claim 6
Dependent Claim
28 words
In the method of claim 1 wherein the surface is the skin of a human, and applying the citric acid solution by massaging the skin with said solution.
Claim 7
Dependent Claim
19 words
In the method of claim 5 wherein the skin is the gingiva, and applying the solution by an applicator.
Claim 8
Dependent Claim
22 words
In the method of claim 5 wherein the skin is on the hands, and applying the solution by washing the hands therein.
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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) | 1982-07-23 | 1983-01-22 | 1983-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-07-23 | 1987-01-22 | 1987-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-07-23 | 1991-01-22 | 1991-07-24 | $7700.00 | Window Closed / Lapsed |