Patent US1531233A successfully refreshed from Google Patents.
Patent US4793809A successfully refreshed from Google Patents.
US4793809A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fiber filled dental porcelain
Assignee: Myron International Inc
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Filing: 1987-05-21
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Granted: 1988-12-27
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Expires: 2007-05-21
Abstract
Abstract Improved dental porcelain compositions and resultant fused porcelain dental restorations are provided which exhibit enhanced strength properties as compared with conventional porcelains. The fiber-filled porcelain compositions of the invention are supplemented with zirconium oxide ceramic fibers in relatively minor amounts of less than 5% by weight. The reinforcing fibers are advantageously predominantly zirconium oxide, and have a relatively short average length of from about 1/32 to 1/4 of an inch. These fibers are normally randomly oriented and homogeneously dispersed throughout the fiber-filled porcelain composition, in order to give a reinforcing fiber network. A completed restoration in accordance with the invention would typically include a core portion formed of the fiber filled porcelain, with the outer portion of the restoration being fabricated from conventional non-fiber reinforced porcelain.
Inventors
- 👤 Mark A. Sigler
- 👤 Timothy J. Sigler
- 👤 Delbert E. Day
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:39
CPC Classifications
A; A61; A61K; A61K6/00; A61K6/80; A61K6/802; A61K6/807; A61K6/15; A61K6/17; A61K6/70; A61K6/78; A61K6/813; A61K6/818; A61K6/82; A61K6/822
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
136 words
A dental restoration comprising a porcelain body selected from the group consisting of inlays, onlays, crowns and pontics having at least a core portion thereof formed of fused dental porcelain having a total fiber content of from about 1 to 4% by weight based upon the weight of the core portion and dispersed in the core portion, at least 25% by weight of said total fiber content being zirconium oxide ceramic fibers having a zirconium oxide content of at least about 50% by weight, said dental restoration further including an outer portion disposed about said core portion and being formed of non-fiber filled dental porcelain, the dental porcelain making up said core and outer portions including a major amount of SiO 2 , and respective smaller quantities of Al 2 O 3 and K 2 O.
Claim 2
Dependent Claim
136 words
A dental restoration comprising a porcelain body selected from the group consisting of inlays, onlays, crowns and pontics having at least a core portion thereof formed of fused dental porcelain having a total fiber content of from about 1 to 4% by weight based upon the weight of the core portion and dispersed in the core portion, at least 25% by weight of said total fiber content being zirconium oxide ceramic fibers having a zirconium oxide content of at least about 50% by weight, said dental restoration further including an outer portion disposed about said core portion and being formed of non-fiber filled dental porcelain, the dental porcelain making up said core and outer portions including a major amount of SiO 2 , and respective smaller quantities of Al 2 O 3 and K 2 O.
Claim 3
Dependent Claim
19 words
The restoration of claim 1, said fibers being homogeneously dispersed throughout and randomly oriented in said fiber-containing dental porcelain.
Claim 4
Dependent Claim
16 words
The restoration of claim 1, said ceramic fibers being white or essentially colorless in said composition.
Claim 5
Dependent Claim
18 words
The restoration of claim 1, said fibers having an average length of from about 1/32 to 1/4 inch.
Claim 6
Dependent Claim
17 words
lThe restoration of claim 4, said fibers having an average length of about 1/16 of an inch.
Claim 7
Dependent Claim
20 words
The restoration of claim 1, said fibers having an average length to diameter ratio of from about 3 to 75.
Claim 8
Dependent Claim
16 words
The restoration of claim 6, said average length to diameter being from about 7 to 20.
Claim 9
Dependent Claim
22 words
The restoration of claim 1, said dental porcelain making up said core portion including at least about 5% of aluminous oxide 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) | 1991-12-27 | 1992-06-27 | 1992-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-12-27 | 1996-06-27 | 1996-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-12-27 | 2000-06-27 | 2000-12-27 | $7700.00 | Window Closed / Lapsed |