The Adhesion Mechanism of Dental Adhesive Resin to the Alloy: Experimental Evidence of the Deterioration of Bonding Ability due to Adsorbed Water on the Oxide Layer

The effect of a several-molecule thick layer of water adsorbed on the oxide layer was examined for a Co-Cr alloy and 18-8 stainless steel. The alloys were dehydrated by heating to 700°C at 1×10-6 Torr after oxidizing at 500°C in air. Dental adhesive resin containing 4-META was bonded to these alloy surfaces in an atmosphere with no water vapor. In both alloys, the bonding ability for the dehydrated surface is superior to those for the as-heated surface at 500°C. Deterioration of bonding ability between the resin and the alloys due to the adsorbed water on the oxide layer was proved experimentally.