Creep in a palladium-enriched high-copper amalgam.

Palladium additions to a dispersed phase high-copper amalgam have been shown recently to suppress markedly the eta' (Cu6Sn5) concentration and decrease creep. A detailed study of the dental and 24 h creep for Pd containing high-copper amalgams and six commercial controls as a function of applied temperature and stress was performed. One part of Ag-Cu or Ag-Cu-Pd dispersants with substitutions of up to 20wt/o Pd for either Ag or Cu was blended with two parts of traditional amalgam alloy. Various temperatures from 25 to 60 degrees C and stresses from 36 to 72 MPa were applied to the samples during the test. For commercial controls and experimental amalgams with no Pd, creep is a strong function of temperature and stress. The experimental amalgam containing up to 10wt/o Pd, Pd substituted for Ag, demonstrated essentially constant creep over the temperature and stress range applied.