An application of potentiostatic current--time transients to study the corrosion of dental amalgams

Potentiostatic current-time transients obtained during anodic polarization of a conventional dental amalgam and its component phases have been analysed to characterize the possible electrochemical reactions involved in amalgam corrosion. These reactions involve such surface phenomena as adsorption, anodic film formation, film dissolution, etc. which are well reflected in current-time transients. The analysis of these transients from the standpoint of thermodynamics, suggests that the saline corrosion of dental amalgam may occur through the dissolution of the passive anodic films on Sn7Hg(gamma2) and Cu6Sn5 (eta') and the dissolution reaction appears to be related to the formation of tin-oxychloride.