title: Longevity of low- and high-copper amalgams analyzed by preparation class, tooth site, patient age, and operator.
abstract: The purpose of this study was to compare the long-term survivals of two low-copper and three high-copper amalgam alloys, and to analyze four clinical factors for their possible effects on the restoration survivals. Some 1476 polished restorations were placed in hospital patients by a large number of operators and assessed over periods of up to 10 years. There were no significant survival differences found among the high-copper alloys and one low-copper alloy, and their survivals were significantly better than for the other low-copper alloy. These results could not have been reliably predicted from the different compositions and creep values of the alloys. A significant effect on restoration survivals was also found with different operators.
authors.affiliation: Department of Dentistry, University of Adelaide, Australia.
authors.forename: R J
authors.initials: RJ
authors.lastname: Smales
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D016009:Chi-Square Distribution; D003300:Copper; D003723:Dental Amalgam / Q000737:chemistry; D003737:Dental Cavity Preparation; D006801:Humans; D008422:Materials Testing; D008875:Middle Aged; D016019:Survival Analysis; D014783:Viscosity
chemical_list: D003300:Copper; D003723:Dental Amalgam