Abstract
A dental adhesive resin containing 4-META was bonded to three different surface states, an as-polished surface and two oxidized surfaces, of a 70 mass % Co-Cr alloy. The surface structure of the alloys was analyzed by ESCA and reflection electron diffraction. The relationship between the bonding strength and surface structures is discussed on the basis of the adhesion mechanism models.
A several-molecule thick layer of H2O which is adsorbed on the Co3O4 layer of the oxidized surfaces lowers the bonding strength. This explains why the bonding strength of the resin on the as-polished surface, which is an amorphous passive film, is superior to the oxidized surfaces which are mainly composed of Co3O4.
