Patent US4661071A successfully refreshed from Google Patents.
US4661071A
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Vacuum sintered powder alloy dental prosthetic device and oven to form same
Assignee: Pentron Corp
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Filing: 1984-06-21
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Granted: 1987-04-28
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Expires: 2004-06-21
Abstract
Abstract An alloyed metal dental prosthetic device, such as a coping, of an alloy dental reconstructive element, is formed from a liquid phase sintered powdered metal alloy at elevated temperatures of about 1000°-1300° C. under a high level of vacuum of about 10 to 1000 microns of Hg. A special oven is devised which will achieve this high level of vacuum in a rapid efficient manner. The resultant metal prosthetic device has the density of at least that found in commercial cast prosthetic devices.
Inventors
- 👤 A. Milton Bell
- 👤 Murray G. Gamberg
- 👤 Ronald Kurzeja
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:05
CPC Classifications
A; A61; A61C; A61C13/00; A61C13/0003; A61K; A61K6/00; A61K6/80; A61K6/84; A61K6/844
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
96 words
A method for forming a dental restorative element comprising: (a) forming an impression of a surface; (b) mixing a refractory material; (c) filling the impression with said refractory material to form a die preform; (d) separating the die preform from the impression; (e) firing the refractory material to form a solid die having a replicate of the surface; (f) covering the surface replicate with a powdered metal alloy; (g) drawing vacuum to 10 to 1000 microns Hg: (h) firing the alloy to sinter the alloy in the liquid phase to form a component of the element.
Claim 2
Independent Claim
96 words
A method for forming a dental restorative element comprising: (a) forming an impression of a surface; (b) mixing a refractory material; (c) filling the impression with said refractory material to form a die preform; (d) separating the die preform from the impression; (e) firing the refractory material to form a solid die having a replicate of the surface; (f) covering the surface replicate with a powdered metal alloy; (g) drawing vacuum to 10 to 1000 microns Hg: (h) firing the alloy to sinter the alloy in the liquid phase to form a component of the element.
Claim 3
Dependent Claim
16 words
The method of claim 1, wherein step (g) is at about 10 to 100 microns Hg.
Claim 4
Dependent Claim
15 words
The method of claim 1, wherein step (h) is at 1000° C. to 1400° C.
Claim 5
Dependent Claim
15 words
The method of claim 1, said formed component having a porosity less than about 1.50%.
Claim 6
Dependent Claim
15 words
The method of claim 1, said formed component having a porosity less than about 1.00%.
Claim 7
Dependent Claim
20 words
The method of claim 1, where the powdered metal of step (f) comprises particulates of from 5 to 90 microns.
Claim 8
Dependent Claim
34 words
The method of claim 1 wherein the powdered metal of step (f) comprises particles from about 5 to about 90 microns in size and a binder to make a paste as a self-supporting preform.
Claim 9
Dependent Claim
22 words
The method of claim 7, wherein the component of the element is permanent and is formed in less than about 11/2 hours.
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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) | 1990-04-27 | 1990-10-27 | 1991-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-27 | 1994-10-27 | 1995-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-27 | 1998-10-27 | 1999-04-28 | $7700.00 | Window Closed / Lapsed |