Patent US4469477A successfully refreshed from Google Patents.
US4469477A
Expired / Lapsed
US
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Dental prosthesis
Assignee: Smith and Nephew PLC
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Filing: 1983-03-24
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Granted: 1984-09-04
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Expires: 2003-03-24
Abstract
Abstract A dental prosthesis which has the whole or part of its surface which is in contact with the mucous membrane of the mouth coated with a soft, hydrophilic polyurethane is provided. The polyurethane coating has a thickness of from 0.1 to 3.00 mm when hydrated. The polyurethane is applied to the prosthesis from a non-aqueous solvent in an anhydrous state and is subsequently hydrated by soaking in water. The polyurethane is a reaction product of a mixture of polyether polyols and a di-isocyanate using an alkenediol as a chain extender. The polyurethane contains from 5 to 40% water when hydrated.
Inventors
- 👤 William D. Potter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:51
CPC Classifications
A; A61; A61C; A61C13/00; A61C13/0025; A61K; A61K6/00; A61K6/20
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
68 words
A dental prosthesis having at least part of the surface of the prosthesis which contacts the mucous membrane of the mouth coated with a soft polymeric lining characterized in that the soft polymeric lining is produced by coating the prosthesis with a hydrophilic linear polyether polyurethane and hydrating the coating with water to a thickness of 0.1 to 3.0 mm and a water content of 20 to 30%.
Claim 2
Dependent Claim
68 words
A dental prosthesis having at least part of the surface of the prosthesis which contacts the mucous membrane of the mouth coated with a soft polymeric lining characterized in that the soft polymeric lining is produced by coating the prosthesis with a hydrophilic linear polyether polyurethane and hydrating the coating with water to a thickness of 0.1 to 3.0 mm and a water content of 20 to 30%.
Claim 3
Dependent Claim
20 words
A dental prosthesis as claimed in claim 1 in which the coating has a thickness of 0.5 to 2.5 mm.
Claim 4
Dependent Claim
58 words
A dental prosthesis as claimed in claim 1 in which the ether units of the hydrophilic linear polyether polyurethane contain poly(ethylene) glycol derivable blocks and poly[(prop- or but-)ylene] glycol derivable blocks in the mole ratio of 1:2 to 1:10 and ethane diol wherein the mole ratio of ethane diol to polyglycol derivable blocks is from 5:2 to 1:3.
Claim 5
Dependent Claim
20 words
A dental prosthesis as claimed in claim 3 in which the hydrophilic linear polyether polyurethane employs 4,4'-dicyclohexyl methane di isocyanate.
Claim 6
Dependent Claim
30 words
A dental prosthesis as claimed in claim 1 wherein the coating is applied to the surface of the prosthesis by painting from a solution of the hydrophilic linear polyether polyurethane.
Claim 7
Dependent Claim
53 words
A process for coating a surface of a dental prosthesis with a soft polymeric lining material which comprises applying to the surface a hydrophilic linear polyether polyurethane from an anhydrous solution of the polymer and hydrating the polyurethane to form a layer 0.1 to 3.0 mm thick and containing 20 to 30% water.
Claim 8
Dependent Claim
53 words
A process for coating a surface of a dental prosthesis with a soft polymeric lining material which comprises applying to the surface a hydrophilic linear polyether polyurethane from an anhydrous solution of the polymer and hydrating the polyurethane to form a layer 0.1 to 3.0 mm thick and containing 20 to 30% water.
Claim 9
Dependent Claim
38 words
A process as claimed in claim 6 in which the hydrophilic linear polyether polyurethane is applied to the surface by painting from an ethanolic solution of the hydrophilic polyurethane which contains from 1 to 15% of said polyurethane.
References Cited (Backward Citations)
US4088500A
Cited
US3822238A
Cited
US3930076A
Cited
GB2027043A
Cited
US4251215A
Cited
GB2093190A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-09-04 | 1988-03-05 | 1988-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-04 | 1992-03-05 | 1992-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-04 | 1996-03-05 | 1996-09-04 | $7700.00 | Window Closed / Lapsed |