Patent US3901693A successfully refreshed from Google Patents.
US3901693A
Expired / Lapsed
US
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Method of preparing dental restorative material
Assignee: Dentsply Research and Development Corp
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Filing: 1973-07-11
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Granted: 1975-08-26
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Expires: 1993-07-11
Abstract
Abstract Dental amalgam material and method of making the same in which a silver alloy particle is formed and coated with gold. Upon the addition of mercury, the gold coating retards the formation of the silver alloy-mercury amalgam, thus extending working time.
Inventors
- 👤 Donald Timothy Wolf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 13:03
CPC Classifications
C; C22; C22C; C22C7/00; A; A61; A61K; A61K6/00; A61K6/80; A61K6/84; A61K6/847; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12771; Y10T428/12861; Y10T428/12889; Y10T428/12896
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
44 words
A METHOD OF MAKING A DENTAL AMALGAM COMPRISING THE STEPS OF: A. PROVIDING A PLURALITY OF SILVER-TIN ALLOY SPHERES, B. COATING THE INDIVIDUAL SILER-TIN ALLOY SPHERES COMPLETELY WITH GOLD, AND C. TRITURARING THE GOLD COATED SILVER-TIN ALLOY SPHERES WITH MERCURY TO FORM AN AMALGAM.
Claim 2
Independent Claim
44 words
A METHOD OF MAKING A DENTAL AMALGAM COMPRISING THE STEPS OF: A. PROVIDING A PLURALITY OF SILVER-TIN ALLOY SPHERES, B. COATING THE INDIVIDUAL SILER-TIN ALLOY SPHERES COMPLETELY WITH GOLD, AND C. TRITURARING THE GOLD COATED SILVER-TIN ALLOY SPHERES WITH MERCURY TO FORM AN AMALGAM.
Claim 3
Dependent Claim
55 words
The invention of claim 1 wherein the particles comprise up to 30% by weight of particles between about 30 microns to about 60 microns; between 40 to 70% by weight of particles between about 10 microns to about 44 microns; and between 30 to 60% by weight of particles of less than about 10-15 microns.
Claim 4
Dependent Claim
25 words
The invention of claim 1 wherein the silver-tin alloy spheres also contain a small amount of one or more of the following: copper, zinc, mercury.
Claim 5
Dependent Claim
19 words
The invention of claim 1 wherein mercury is added to comprise about 30 to about 50% of the amalgam.
Claim 6
Dependent Claim
19 words
The invention of claim 1 wherein mercury is added to comprise about 38 to about 44% of the amalgam.
Claim 7
Dependent Claim
20 words
The invention of claim 1 wherein the silver-tin alloy spheres are coated with from about 0.05 to about 3% gold.
Claim 8
Dependent Claim
16 words
The invention of claim 1 wherein the spherical cores are under approximately 60 microns in size.
Claim 9
Independent Claim
141 words
A method for preparing dental restorative material having a controlled working time prior to set comprising the steps of: a. forming a test group of alloy spheres; b. sub-dividing the test group; c. coating each sub-divided test group with a different thickness of gold; d. applying an amalgamating substance to the spheres of each test group; e. measuring the working time elapsed from the application of the amalgamating material to the penetration thereof through the gold coatings of the spheres and until the alloys of the spheres set in each test group; f. forming a working group of alloy spheres; g. applying to said working group of spheres a gold coating having a thickness corresponding to the aforesaid test group most approximating the desired working time, prior to final setting of the coated spheres by application of an amalgamating material thereto.
Claim 10
Independent Claim
141 words
A method for preparing dental restorative material having a controlled working time prior to set comprising the steps of: a. forming a test group of alloy spheres; b. sub-dividing the test group; c. coating each sub-divided test group with a different thickness of gold; d. applying an amalgamating substance to the spheres of each test group; e. measuring the working time elapsed from the application of the amalgamating material to the penetration thereof through the gold coatings of the spheres and until the alloys of the spheres set in each test group; f. forming a working group of alloy spheres; g. applying to said working group of spheres a gold coating having a thickness corresponding to the aforesaid test group most approximating the desired working time, prior to final setting of the coated spheres by application of an amalgamating material thereto.
Claim 11
Dependent Claim
11 words
The invention of claim 8 wherein the amalgamating material is mercury.
Claim 12
Independent Claim
86 words
A method for making dental restorations comprising the steps of: a. manufacturing spherical particles having spherical inner alloy cores individually covered with substantially uniform gold coatings, said particles having a capacity to snap set after a period of working time upon trituration with mercury, said working time being variable in accordance with the length of trituration; b. determining the working time required to complete the restoration; and c. triturating mercury and the coated particles for a preselected length of time to produce the required working time.
Claim 13
Independent Claim
86 words
A method for making dental restorations comprising the steps of: a. manufacturing spherical particles having spherical inner alloy cores individually covered with substantially uniform gold coatings, said particles having a capacity to snap set after a period of working time upon trituration with mercury, said working time being variable in accordance with the length of trituration; b. determining the working time required to complete the restoration; and c. triturating mercury and the coated particles for a preselected length of time to produce the required working time.
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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) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |