Patent US3934348A successfully refreshed from Google Patents.
US3934348A
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Method of forming a porcelain crown
Assignee: Individual
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Filing: 1975-01-02
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Granted: 1976-01-27
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Expires: 1995-01-02
Abstract
Abstract A method of forming a porcelain crown that requires no shoulder, and can be fitted over any type of standard impression made by a dentist. In the method, a laboratory plaster model is made from a dentist's impression and includes male and female dies. The male die has successive layers of materials applied thereupon comprising first a 0.002 gauge platinum film followed successively by a first layer of gold crust, a second layer of gold crust and opaque porcelain, upon which a regular porcelain is applied that fits the female die with the regular porcelain receiving thereafter a final application of glazing powder. The crown is baked between each step of the process.
Inventors
- 👤 Bora Janjic
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:12
CPC Classifications
A; A61; A61C; A61C13/00; A61C13/0003; A61C5/00; A61C5/70; A61C5/73; A61C5/77
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
91 words
A method for forming a dental crown on a crown model made from a dentist's impression, including the steps of forming male and female dies on the model in hard dental plaster, applying a 0.002 inch gauge platinum film to the male die in form fitting relation, brushing a layer of gold crust on the platinum film, baking the crown, brushing a second layer of gold crust on the crown, baking the crown, applying a regular porcelain to the crown conformed to the contour of the female die, baking the crown,
Claim 2
Independent Claim
91 words
A method for forming a dental crown on a crown model made from a dentist's impression, including the steps of forming male and female dies on the model in hard dental plaster, applying a 0.002 inch gauge platinum film to the male die in form fitting relation, brushing a layer of gold crust on the platinum film, baking the crown, brushing a second layer of gold crust on the crown, baking the crown, applying a regular porcelain to the crown conformed to the contour of the female die, baking the crown,
Claim 3
Dependent Claim
26 words
The method as set forth in claim 1, wherein the baking step after applying the first layer of gold crust consists of baking in a porcelain
Claim 4
Dependent Claim
26 words
The method as set forth in claim 2, wherein the baking step after applying the second layer of gold crust consists of baking in the furnace
Claim 5
Dependent Claim
68 words
The method as set forth in claim 3 wherein the baking step after applying the opaque porcelain consists of baking in the furnace in air starting with a temperature of 800°F. then increasing to 1200°F., and then bake in the furnace in a vacuum starting with a temperature of 1200°F. then increasing to 1750°F., release the vacuum and continue to bake in air to a final temperature of
Claim 6
Dependent Claim
68 words
The method as set forth in claim 4, wherein the baking step after applying the regular porcelain consists of baking in the furnace in air beginning with a temperature of 800°F. and increasing to 1200°F., and then bake in the furnace in a vacuum beginning with a temperature of 1200°F. and increasing to 1650°F., release the vacuum and continue to bake in air to a final temperature of
Claim 7
Dependent Claim
38 words
The method as set forth in claim 5, wherein the baking step after applying the glazing powder consists of baking in the furnace in air beginning with a temperature of 800°F. and increasing to between 1710° and 1720°F.
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) | 1979-01-26 | 1979-07-28 | 1980-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-26 | 1983-07-28 | 1984-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-26 | 1987-07-28 | 1988-01-27 | $7700.00 | Window Closed / Lapsed |