Effect of Time at 37°C on the Creep and Metallurgical Characteristics of Amalgam

Abstract

When aged at 37°C for six months, dental amalgam exhibits a marked decrease in the property of creep. The objective of this study was to investigate the relationship between this decrease in creep and selected metallurgical characteristics. The formation of β₁ (Ag-Hg), the grain size of γ₁ (Ag-Hg), and the composition of γ₁ were chosen for investigation. Creep was determined according to ADA Specification test No. 1, β₁ was measured by x-ray diffraction, and γ₁ grain size and γ₁ composition were determined by electron-probe microanalysis. The results showed that the decrease in creep was related to β₁ formation and not to changes in either γ₁ grain size or γ₁ composition.

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