US3871876A - Dental Amalgam - Google Patents

Dental Amalgam Download PDF

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Publication number
US3871876A
US3871876A US451840A US45184074A US3871876A US 3871876 A US3871876 A US 3871876A US 451840 A US451840 A US 451840A US 45184074 A US45184074 A US 45184074A US 3871876 A US3871876 A US 3871876A
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United States
Prior art keywords
tin
silver
copper
ratio
amalgamable
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US451840A
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English (en)
Inventor
Kamal Asgar
Steven H Reichman
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ALLEGHENY INTERNATIONAL ACCEPTANCE Corp
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Individual
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Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US451840A priority Critical patent/US3871876A/en
Priority to CA216,699A priority patent/CA1039538A/en
Priority to AU77153/75A priority patent/AU478176B2/en
Priority to IT19378/75A priority patent/IT1028449B/it
Priority to DE2505934A priority patent/DE2505934C3/de
Priority to JP2142775A priority patent/JPS5435860B2/ja
Priority to SE7502497A priority patent/SE425049B/xx
Priority to NL7502941.A priority patent/NL167318C/xx
Priority to BR1521/75A priority patent/BR7501521A/pt
Priority to FR7508437A priority patent/FR2264521B1/fr
Application granted granted Critical
Publication of US3871876A publication Critical patent/US3871876A/en
Priority to GB1123875A priority patent/GB1476100A/en
Assigned to AL-INDUSTRIAL PRODUCTS, INC. reassignment AL-INDUSTRIAL PRODUCTS, INC. SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SPECIAL METALS CORPORATION A DE CORP
Assigned to CITICORP INDUSTRIAL CREDIT, INC., BOND COURT BLDG., STE. 615, 1300 E. 9TH ST., CLEVELAND, OH. 44114 reassignment CITICORP INDUSTRIAL CREDIT, INC., BOND COURT BLDG., STE. 615, 1300 E. 9TH ST., CLEVELAND, OH. 44114 SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SPECIAL METALS CORPORATION
Assigned to ALLEGHENY INTERNATIONAL ACCEPTANCE CORPORATION reassignment ALLEGHENY INTERNATIONAL ACCEPTANCE CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: AL- INDUSTRIAL PRODUCTS INC.
Assigned to HELLER FINANCIAL, INC. reassignment HELLER FINANCIAL, INC. SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SPECIAL METALS CORPORATION
Assigned to SPECIAL METALS CORPORATION reassignment SPECIAL METALS CORPORATION RELEASED BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: CITICORP INDUSTRIAL CREDIT, INC.
Assigned to SPECIAL METALS CORPORATION reassignment SPECIAL METALS CORPORATION RELEASED BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: AL-INDUSTRIAL PRODUCTS, INC., A CORP. OF PA, ALLEGHENY INTERNATIONAL, INC., A CORP. OF PA
Assigned to SPECIAL METALS CORPORATION reassignment SPECIAL METALS CORPORATION RELEASED BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: HELLER FINANCIAL, INC.
Anticipated expiration legal-status Critical
Assigned to CREDIT LYONNAIS NEW YORK BRANCH reassignment CREDIT LYONNAIS NEW YORK BRANCH SECURITY INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: SPECIAL METALS CORPORATION
Expired - Lifetime legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/0466—Alloys based on noble metals
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K6/00—Preparations for dentistry
    • A61K6/80—Preparations for artificial teeth, for filling teeth or for capping teeth
    • A61K6/84—Preparations for artificial teeth, for filling teeth or for capping teeth comprising metals or alloys
    • A61K6/847—Amalgams
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C7/00—Alloys based on mercury
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S75/00—Specialized metallurgical processes, compositions for use therein, consolidated metal powder compositions, and loose metal particulate mixtures
    • Y10S75/955—Producing dental product

Definitions

  • silver-base alloys suitable for forming amalgams in accordance with American Dental Association specifications contain from about 26% to about 28% tin, about 1% to about 2% zinc, about 2% to about 4% copper, with the balance essentially all silver.
  • the quantity of copper should be restricted to a maximum of about 6% due to the tendency of dental amalgams incorporating greater quantities of copper to corrode and/or discolor in actual use.
  • quantities of copper in excess of about 6% are known to improve the compressive strength of the resultant dental amalgam.
  • the general requirements of a dental amalgam include a retention of shape, color and appearance; a biological compatibility, a restoration of the tooth to its original function, and a long durable operating life.
  • creep resistance is perhaps the single most important mechanical property followed by compressive strength as it relates to failure or fracture of dental restorations.
  • the present invention provides for an amalgamable silver alloy containing amounts of copper substantially greater than those heretofore considered useable which improves not only the resistance of the dental amalgam toward corrosion and/or discoloration, but also provides for substantially superior mechanical properties, including increased resistance to dynamic creep.
  • an amalgamable silver alloy powder derived from a microcasting of a molten mass of the alloy, such as by fluid atomization techniques or the like, and wherein each particle is of substantially the same composition and is further characterized by having a gradient composition in which the concentration of the individual alloying constituents changes on moving in a direction from the surface of the particle toward the center thereof.
  • the amalgamable powder contains tin and copper in combination with silver as the essential alloying constituent and wherein the silver-to-tin ratio is controlled from about 1.8:1 to about 3.0: l while the tin-to-copper ratio is controlled from about 1:1 to
  • the amalgamable silver alloy powder contains from about 8% to about 27% copper, from about 20% to about 32% tin, with the balance consisting essentially of silver but, in any event, a minimum of 47% silver.
  • the alloy powder can also contain up to about 2% zinc without any adverse effects.
  • the powder particles are of an average size less than about 100 microns and preferably range from about 5 microns to about 44 microns.
  • the dental amalgam is prepared employing the amalgamable silver alloy powder by admixture with mercury in an amount of from about 42% up to about 54% and preferably in an amount such that mercury in the final product is present from about 46% to about 50% by weight.
  • the ratio of silver-to-tin is broadly controlled within the range of about 1.8 up to about 3.0, while the permissible ratios of tin-to-copper are from about 1 to about 3.
  • the minimum percentages are specified with the recognition that when any one of the three is at the minimum level, one or both of the remaining alloys are present in amounts greater than their respective minimums in order that the total percent is 100. The foregoing is also applicable to the preferred percentages of these three alloying constituents as set forth in Table 1.
  • the relative proportions of the three metals are set forth in terms of their weight ratios in which the silver-to-tin ratio preferably is controlled within a range of about 2.2 to about 2.6, while the tin-to-copper ratio is preferably controlled within a range of about 1.5 to about 2.5. It is also contemplated that zinc can be in- 3 cluded in amounts up to about 2% by weight of the total alloy.
  • the amalgamable silver alloy powder is derived by I a microcasting technique in which molten fine-sized droplets of the desired composition "are cooled in a manner to effect a progressive solidification during the cooling commencing on the surface and moving inwardly thereof.
  • the differential cooling and solidification rate of each droplet contributes toward a stratification or composition gradient in the final solidifed particle which is at least in part responsible for the unexpected improved mechanical and chemical properties of dental amalgams prepared therefrom.
  • the microcasting of a molten mass of the silver alloy can be achieved by a variety of techniques including gas atomization, airless spraying and centrifugal fragmentation for effecting a subdivision of the molten mass into a plurality of fine-sized liquid droplets which are all of substantially the same composition.
  • gas atomization technique has been found particularly satisfactory and a specific embodiment thereof is described in US. Pat. No. 3,253,783, the teachings of which are incorporated herein by reference.
  • a molten stream of the metal alloy passes downwardly and is atomized in response to the impingement of a conically-shaped vortex of gas and wherein the resultant droplets progressively solidify as they fall downwardly through the collection chamber.
  • Metal powder produced in accordance with the arrangement described in the aforementioned patent under proper operating conditions generally is of a spherical configuration and where the predominant portion thereof is of a particle size within the desired range.
  • the amalgamable powder can be of any particle configuration, although particles of a substantially spherical configuration are preferred
  • the powder can be of an average particle size of less than about 100 microns, although powders having average particle sizes ranging from about 45 microns to about 5 microns are usually preferred,
  • the contact of the molten silver alloy with'the oxygen in the atomizing gas occasions the formation of undesirable oxides on the particle surfaces. While such oxides can subsequently be reduced by heating the powder in a reducing atmosphere, such as hydrogen, for example, it is preferred to employ a substantially inert gas, such as a substantially dry argon, nitrogen or helium gas, for effecting the atomization of the powder and also as the cooling medium within the powder collection chamber.
  • a substantially inert gas such as a substantially dry argon, nitrogen or helium gas
  • the amalgamable powder of the desired composition and particle size can be employed for forming a dental amalgam at the time required by admixture with from about 42% up to about 54% mercury and, more usually, from about 46% to about 50% mercury.
  • the wetting of the particle surfaces with mercury initiates the amalgamation reaction, whereby the intermetallic compounds formed by a consumption of the surface strata of the particles serves to bond the residual unreacted particle cores to each other, forming a matrix characterized as a continuous phase of amalgam, having interspersed therethrough discrete discontinuous phases of the unreacted particle cores.
  • the tin-mercury intermetallic compound comprises the weakest alloy with respect to compressive strength and also is the most susceptible to corrosion and/or discoloration.
  • each of the particles contains a higher concentration of silver and copper with the inner core of the particle comprising a tinrich phase. This minimizes the formation of detrimental tin intermetallic compounds, whereby the properties of the resultant dental amalgam are substantially improved.
  • the foregoing is substantiated by microprobe analyses ofthe spherical alloy particles employing x-ray beams which show a variation in the composition between the inner portions of each particle relative to the peripheral portions thereof.
  • the range of composition values obtained by microprobe analyses of large amalgam alloy particles are set forth in Table 2.
  • amalgamable silver alloy powder of the present invention and the improved properties of amalgams prepared therefrom, the following specific example is provided. It willbe understood that the example is included solely for illustrative purposes and is not intended to be limiting of the scope of the invention as herein described and as set forth in the subjoined claims.
  • An amalgamable silver alloy powder is prepared by the argon atomization of a molten mass of material containing a silver-to-tin ratio of 2.23:1 and a tin-tocopper ratio of 2.10:1, resulting in an alloy consisting essentially of 13% copper, 27% tin and 60% silver.
  • the resultant powder particles are generally of a spherical configuration and the collected powder is screened to separate and recover particles of an average particle size ranging from 44 microns to about 5 microns. The balance of the powder particles are recycled.
  • the resultant heat-treated and washed amalgamable powder is triturated for ten seconds with approximately 46% mercury, whereafter the mixture is shaped into a test specimen and allowd to set for a period of 7 days.
  • Test evaluations of the resultant dental amalgam test specimen reveal a compressive strength of greater than about 75,000 psi, a creep resistance of less than 0.20% in 3 hours, and an observable resistance to tarnish and corrosion.
  • An amalgamable silver alloy powder in which each of the particles are of substantially the same composition and consist essentially of silver, tin and copper; said silver and tin being present at a ratio of from about 1.811 to about 30:1 and said tin and copper being present at a ratio of about 1:1 up to 3:1, said powder further characterized as being of an average particle size less than about microns and wherein each particle is of a gradient composition on moving from the surface toward the core thereof.
  • amalgamable silver alloy powder as defined in claim 1 in which said ratio of silver-to-tin ranges from about 2.2 to about 2.6.
  • amalgamable silver alloy powder as defined in claim 1 in which the average particle size thereof ranges from about 45 microns to about 5 microns.
  • a dental amalgam consisting essentially of a continuous matrix composed of an amalgam having interspersed therethrough a plurality of discrete phases chemically bonded by said continuous phase into an integral matrix, said discrete phases comprising particles of an alloy consisting essentially of silver, tin and copper and wherein the particles are of a gradient composition on moving from the surfaces thereof toward their center, said continuous phase comprising intermetallic compounds of mercury with silver, tin and copper; said dental amalgam containing from about 42% to about 54% mercury, and said silver, tin and copper being present in amounts so as to provide a ratio of silver-totin of from about 1.8 up to about 3.0 and tin-to-copper of from about 1:1 up to 3:1.
  • amalgamable silver alloy powder as defined in claim 1 further including up to 2% zinc.

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  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Organic Chemistry (AREA)
  • Metallurgy (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Veterinary Medicine (AREA)
  • Public Health (AREA)
  • General Health & Medical Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • Epidemiology (AREA)
  • Plastic & Reconstructive Surgery (AREA)
  • Dental Preparations (AREA)
  • Powder Metallurgy (AREA)
US451840A 1974-03-18 1974-03-18 Dental Amalgam Expired - Lifetime US3871876A (en)

Priority Applications (11)

Application Number Priority Date Filing Date Title
US451840A US3871876A (en) 1974-03-18 1974-03-18 Dental Amalgam
CA216,699A CA1039538A (en) 1974-03-18 1974-12-23 Dental amalgam and method of making same
AU77153/75A AU478176B2 (en) 1974-03-18 1975-01-07 Dental amalgam and method of making same
IT19378/75A IT1028449B (it) 1974-03-18 1975-01-17 Amalgama per odontoiatria e metodo per la preparazione dello stesso
DE2505934A DE2505934C3 (de) 1974-03-18 1975-02-13 Verfahren zur Herstellung eines amalgamierbaren Legierungspulvers und Verwendung desselben für die Herstellung von Dentalamalgam
JP2142775A JPS5435860B2 ( ) 1974-03-18 1975-02-20
SE7502497A SE425049B (sv) 1974-03-18 1975-03-06 Amalgamerbart silverlegeringspulver
NL7502941.A NL167318C (nl) 1974-03-18 1975-03-12 Werkwijze ter bereiding van een poedervormige amalga- meerbare zilverlegering.
BR1521/75A BR7501521A (pt) 1974-03-18 1975-03-14 Po de liga de prata amalgamavel e amalgama dental
GB1123875A GB1476100A (en) 1974-03-18 1975-03-18 Dental amalgams
FR7508437A FR2264521B1 ( ) 1974-03-18 1975-03-18

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US451840A US3871876A (en) 1974-03-18 1974-03-18 Dental Amalgam

Publications (1)

Publication Number Publication Date
US3871876A true US3871876A (en) 1975-03-18

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US451840A Expired - Lifetime US3871876A (en) 1974-03-18 1974-03-18 Dental Amalgam

Country Status (10)

Country Link
US (1) US3871876A ( )
JP (1) JPS5435860B2 ( )
BR (1) BR7501521A ( )
CA (1) CA1039538A ( )
DE (1) DE2505934C3 ( )
FR (1) FR2264521B1 ( )
GB (1) GB1476100A ( )
IT (1) IT1028449B ( )
NL (1) NL167318C ( )
SE (1) SE425049B ( )

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3954457A (en) * 1975-04-28 1976-05-04 Gary Maurice Weikel Dental amalgam
US3975192A (en) * 1975-03-28 1976-08-17 Sybron Corporation Dental alloy and amalgam
US3985558A (en) * 1975-03-28 1976-10-12 Sybron Corporation Dental alloy and amalgam
US3997328A (en) * 1975-12-29 1976-12-14 Engelhard Minerals & Chemicals Corporation Dental amalgams
US3997327A (en) * 1975-12-29 1976-12-14 Engelhard Minerals & Chemicals Corporation Dental composition
US3997330A (en) * 1975-12-29 1976-12-14 Engelhard Minerals & Chemicals Corporation Dental amalgams
US3997329A (en) * 1975-12-29 1976-12-14 Engelhard Minerals & Chemicals Corporation Dental composition
US4008073A (en) * 1975-03-14 1977-02-15 Deutsche Gold- Und Silber-Scheideanstalt Vormals Roessler Alloy powder for the production of dental amalgam
US4030918A (en) * 1976-05-27 1977-06-21 Johnson & Johnson Indium containing dental alloy powder
US4080199A (en) * 1976-05-27 1978-03-21 Johnson & Johnson Lathe cut dental alloy powder
FR2377191A1 (fr) * 1977-01-17 1978-08-11 Engelhard Min & Chem Alliage dentaire resistant a la corrosion et presentant des caracteristiques de manipulation ameliorees
US4164419A (en) * 1975-12-22 1979-08-14 Shofu Dental Manufacturing Company, Limited Powdered alloy for dental amalgam
US4226622A (en) * 1978-08-24 1980-10-07 Engelhard Minerals & Chemicals Corporation Corrosion-resistant dental alloy
US4234339A (en) * 1978-08-24 1980-11-18 Engelhard Minerals & Chemicals Corporation Corrosion-resistant dental alloy
US4235631A (en) * 1978-08-24 1980-11-25 Engelhard Minerals & Chemicals Corporation Corrosion-resistant dental alloy having improved handling characteristics
EP0033628A2 (en) * 1980-01-31 1981-08-12 Macrodent S.A. A product to be used in dental amalgams
US4374085A (en) * 1980-05-29 1983-02-15 Special Metals Corporation Silver-tin-copper-palladium alloy and amalgam thereof
US4479823A (en) * 1982-10-30 1984-10-30 Blendax-Werke R. Schneider Gmbh & Co. Process for the production of silver-tin master alloys for dental amalgams
US4664855A (en) * 1985-11-12 1987-05-12 Special Metals Corporation Method for producing amalgamable alloy
US4664629A (en) * 1983-06-27 1987-05-12 Dentsply Research & Development Corp. Dental composition mixture
US5091114A (en) * 1988-08-23 1992-02-25 Asahi Kasei Kogyo Kabushiki Kaisha Conductive metal powders, process for preparation thereof and use thereof
US5354353A (en) * 1993-10-28 1994-10-11 Special Metals Corporation Amalgamable composition and method of production
US5490870A (en) * 1993-10-28 1996-02-13 Special Metals Corporation Amalgamable composition and method of production
FR2772265A1 (fr) * 1997-12-12 1999-06-18 Schiller Henri Amalgame dentaire a taux reduit en mercure et procede de fabrication d'un tel amalgame
US6458180B1 (en) * 2001-01-10 2002-10-01 Jiin-Huey Chern Lin Amalgamatable dental alloy powder having an effect of reducing initial mercury vapor release rate

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0214202Y2 ( ) * 1980-02-20 1990-04-18
WO1995010379A1 (en) * 1993-10-08 1995-04-20 The United States Of America, As Represented By The Secretary Of Commerce Acid assisted cold welding and intermetallic formation and dental applications thereof

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1612782A (en) * 1923-12-19 1926-12-28 Lee S Smith & Son Mfg Company Dental alloy and process of making the same
US1963085A (en) * 1933-08-05 1934-06-19 Arthur W Gray Comminuted alloy
US2281991A (en) * 1938-04-27 1942-05-05 Poetschke Paul Dental amalgam alloy
US3305356A (en) * 1963-08-30 1967-02-21 William V Youdelis Dental amalgam
US3554738A (en) * 1968-05-21 1971-01-12 Victor E Beldham Dental amalgam
US3676112A (en) * 1970-05-19 1972-07-11 Indiana University Foundation Anticariogenic dental amalgam

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1612782A (en) * 1923-12-19 1926-12-28 Lee S Smith & Son Mfg Company Dental alloy and process of making the same
US1963085A (en) * 1933-08-05 1934-06-19 Arthur W Gray Comminuted alloy
US2281991A (en) * 1938-04-27 1942-05-05 Poetschke Paul Dental amalgam alloy
US3305356A (en) * 1963-08-30 1967-02-21 William V Youdelis Dental amalgam
US3554738A (en) * 1968-05-21 1971-01-12 Victor E Beldham Dental amalgam
US3676112A (en) * 1970-05-19 1972-07-11 Indiana University Foundation Anticariogenic dental amalgam

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4008073A (en) * 1975-03-14 1977-02-15 Deutsche Gold- Und Silber-Scheideanstalt Vormals Roessler Alloy powder for the production of dental amalgam
US3975192A (en) * 1975-03-28 1976-08-17 Sybron Corporation Dental alloy and amalgam
DE2612716A1 (de) * 1975-03-28 1976-10-07 Sybron Corp Dental-silberlegierung und silberamalgam
US3985558A (en) * 1975-03-28 1976-10-12 Sybron Corporation Dental alloy and amalgam
US3954457A (en) * 1975-04-28 1976-05-04 Gary Maurice Weikel Dental amalgam
US4164419A (en) * 1975-12-22 1979-08-14 Shofu Dental Manufacturing Company, Limited Powdered alloy for dental amalgam
US3997330A (en) * 1975-12-29 1976-12-14 Engelhard Minerals & Chemicals Corporation Dental amalgams
US3997329A (en) * 1975-12-29 1976-12-14 Engelhard Minerals & Chemicals Corporation Dental composition
US3997327A (en) * 1975-12-29 1976-12-14 Engelhard Minerals & Chemicals Corporation Dental composition
US3997328A (en) * 1975-12-29 1976-12-14 Engelhard Minerals & Chemicals Corporation Dental amalgams
US4030918A (en) * 1976-05-27 1977-06-21 Johnson & Johnson Indium containing dental alloy powder
US4080199A (en) * 1976-05-27 1978-03-21 Johnson & Johnson Lathe cut dental alloy powder
FR2377191A1 (fr) * 1977-01-17 1978-08-11 Engelhard Min & Chem Alliage dentaire resistant a la corrosion et presentant des caracteristiques de manipulation ameliorees
US4226622A (en) * 1978-08-24 1980-10-07 Engelhard Minerals & Chemicals Corporation Corrosion-resistant dental alloy
US4234339A (en) * 1978-08-24 1980-11-18 Engelhard Minerals & Chemicals Corporation Corrosion-resistant dental alloy
US4235631A (en) * 1978-08-24 1980-11-25 Engelhard Minerals & Chemicals Corporation Corrosion-resistant dental alloy having improved handling characteristics
EP0033628A3 (en) * 1980-01-31 1982-05-26 Macrodent S.A. A product to be used in dental amalgams
EP0033628A2 (en) * 1980-01-31 1981-08-12 Macrodent S.A. A product to be used in dental amalgams
US4374085A (en) * 1980-05-29 1983-02-15 Special Metals Corporation Silver-tin-copper-palladium alloy and amalgam thereof
US4479823A (en) * 1982-10-30 1984-10-30 Blendax-Werke R. Schneider Gmbh & Co. Process for the production of silver-tin master alloys for dental amalgams
US4664629A (en) * 1983-06-27 1987-05-12 Dentsply Research & Development Corp. Dental composition mixture
US4664855A (en) * 1985-11-12 1987-05-12 Special Metals Corporation Method for producing amalgamable alloy
US5091114A (en) * 1988-08-23 1992-02-25 Asahi Kasei Kogyo Kabushiki Kaisha Conductive metal powders, process for preparation thereof and use thereof
US5354353A (en) * 1993-10-28 1994-10-11 Special Metals Corporation Amalgamable composition and method of production
US5490870A (en) * 1993-10-28 1996-02-13 Special Metals Corporation Amalgamable composition and method of production
FR2772265A1 (fr) * 1997-12-12 1999-06-18 Schiller Henri Amalgame dentaire a taux reduit en mercure et procede de fabrication d'un tel amalgame
US6458180B1 (en) * 2001-01-10 2002-10-01 Jiin-Huey Chern Lin Amalgamatable dental alloy powder having an effect of reducing initial mercury vapor release rate

Also Published As

Publication number Publication date
AU7715375A (en) 1976-07-08
GB1476100A (en) 1977-06-10
DE2505934C3 (de) 1979-01-04
DE2505934B2 (de) 1978-05-11
IT1028449B (it) 1979-01-30
SE7502497L ( ) 1975-09-19
BR7501521A (pt) 1975-12-23
NL167318B (nl) 1981-07-16
DE2505934A1 (de) 1975-09-25
SE425049B (sv) 1982-08-30
CA1039538A (en) 1978-10-03
FR2264521A1 ( ) 1975-10-17
NL167318C (nl) 1981-12-16
NL7502941A (nl) 1975-09-22
FR2264521B1 ( ) 1978-12-29
JPS50125922A ( ) 1975-10-03
JPS5435860B2 ( ) 1979-11-06

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