title: In vitro tarnish of dental amalgams.
abstract: 1. Tuccillo-Nielsen tarnish test in an effective screening device for dental amalgams. 2. The gamma phase appears to be more tarnish prone in conventional dental amalgams than gamma 1 phase. Although gamma 2 appeared to be tarnish prone, it was difficult to discriminate this phase because of the porosity in the amalgams. 3. The copper-rich phases are the most tarnish prone in high-copper amalgams. Gross examinations of amalgam from additive systems show spotty tarnish, whereas more uniform tarnish appearance is observed in amalgams from single-composition alloys. 4. The amalgams can be graded for in vitro tarnish performance in selected groups like the additive systems and the single-composition alloys.
mesh_terms: D003300:Copper; D003343:Corrosion; D003722:Dental Alloys; D003723:Dental Amalgam; D004563:Electrochemistry; D008628:Mercury; D008669:Metallurgy; D012834:Silver; D013499:Surface Properties; D014001:Tin
chemical_list: D003722:Dental Alloys; D012834:Silver; D014001:Tin; D003300:Copper; D003723:Dental Amalgam; D008628:Mercury