Abstrait

Corrosion of dental alloys for fixed partial denture when exposed to high anodic potentials

Maxime Helfer, Pascal De March, Patrice Berthod

Themetallic alloys used to mechanically strengthen ceramic-metallic dental prosthesismay partly emerge in contact with the saliva present in the buccal milieu. They are then subjected to a possible corrosion by the more or less aerated saliva. Specific electrochemical runswere here performed tomeasure the corrosion rates of several selected dental alloys used in frameworks reinforcing some fixed partial dentures when they are maintained at a high anodic potential in an acidified Fusayama saliva, in order to better knowthe behaviour of these alloys in a saliva which may contain a lot of dissolved oxygen. The initial cyclic polarization runs performed over a large anodic range of potentials allowed choosing, in the E-increasing part of the obtained curves, values of high potential at which alloys were permanently exposed during 3 days. After each experiment the electrolyte was analyzed by ICP measurements to detect the eventual presence of the more or less noble metallic elements initially belonging to the alloys.