Degussa Aktiengesellschaft

Other

Degudent Gmbh

Doris Hathaway

Werner Groll

Gernot Schock

Bernd Kempf

Gernot Schoeck

Lothar Volkl

Rudolf M Wagner

Hans-Martin Ringelstein

Rudi Steinke

Angela Klaus

Manfred Stuemke

Jochen Bauer

Martin Schuster

Bernd Meier

Lothar Voelkl

A dental alloy with a high gold content that is devoid of palladium and copper. To achieve high mechanical stability, the dental alloy contains between 75 and 95 wt. % Au, between 5 and 20 wt. % Pt, between 0.5 and 3.5 wt. % Zn and/or Sn and/or In, between 0.1 and 0.8 wt. % of an element of a group I, in addition to a single particle refiner of a group II. The weight fraction of the element of group I is between 2 and 6 times that of the single particle refiner of group II, and one element of group I is represented by Nb or Ta or Ti or V and the particle refiner of group II is represented by Ir or Rh.

Dental alloy with a high gold content that is devoid of palladium and copper

Gold-palladium alloys with a high gold content for dental applications should, for reasons of biocompatibility, not contain any toxically dubious components. For particularly corrosion-resistant and biocompatible Type 4 alloys, tin is needed as the only base-metal component in amounts between 0.7 and 5.8 wt % if one remains within defined limits in a palladium-tin diagram of FIG. 1, for Pt values less than 2%. Such alloys contain, in addition to gold and tin, 6 to 25 wt % palladium, 0 to 12 wt % platinum and 0 to 2 wt % of at least one of iridium, rhodium and/or ruthenium.

Gold-palladium alloys for dental materials

Gold-free palladium-silver alloys for dentures [dental prostheses] which alloys can be veneered without color changes with dental ceramics and can be easily removed from the mold after the casting contain 45 to 80% by weight palladium, 7 to 50% by weight silver, 0 to 5% by weight gold, 0 to 5% by weight tin, 0 to 5% by weight indium, 0 to 3% by weight zinc, 0 to 2% by weight copper, 0 to 1% by weight ruthenium, iridium and/or rhenium, 0 to 7% by weight gallium, 0 to 5% by weight cobalt and 0 to 3% by weight germanium, whereby of the elements gallium, cobalt and germanium at least two must be present with contents totalling 2 to 9% by weight.

Use of palladium-silver alloys for the manufacture of dentures

Palladium based dental alloys do not show unaesthetic discolorations after ceramic firing if said alloys contain 66-85% by weight palladium, 1-20% by weight gold; 0-4% by weight silver; 0-4% by weight of at least one of platinum, iron and/or cobalt; 0.5-7% by weight of each of gallium, tin and indium, whereby the amount of said components total 9-14% by weight; 0-2% by weight germanium and/or zinc; and 0-1% by weight iridium, ruthenium and/or rhenium.

Palladium based alloy for dental applications

An economical alloyed powder for dental amalgams exhibiting good working properties is obtained from pressed and sintered molded bodies by mechanical comminution. The formed body is produced by mixing and pressing powders of elemental silver, copper and tin with a subsequent sintering between 150.degree. C. and the solidus temperature of the alloy being formed. The sintering is performed until a homogeneous distribution of the tin has been achieved in the silver and copper particles.

Method of producing alloyed powders for dental amalgams

Economical but readily workable palladium alloys for baking on dental ceramics consist of 60 to 80% palladium, 0 to 8% gold, 0 to 5% platinum, 0 to 1% ruthenium and/or rhenium, 2 to 20% copper, 1 to 12% tin and/or indium, 0.2 to 5% of at least one of the elements tungsten, molybdenum, niobium, and tantalum, and 0 to 15% cobalt, with the proviso that the sum of tin and indium must be between 5 and 14%.

Use of silver-free palladium alloys for firing on dental ceramics

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Hanau, Germany

Doris Hathaway