Adhesion of Adhesive Resin to Dental Precious Metal Alloys

Part II The Relationship between Surface Structure of Au-In Alloys and Adhesive Ability with 4-META Resin

抄録

Adhesion of 4-META to Au-In alloy was improved by adding In equivalent to 15% of Au content. On the basis of the results of Au-In alloys analyzed by XPS, the present study investigated the reason why adhesion of the Au-In alloy was improved. The O 1s spectrum could be separated into three oxygen chemical states, In₂O₃, chemisorbed H₂O, and physisorbed H₂O. The amount of chemisorbed H₂O decreased remarkably with increasing amount of In. It is considered that the poor adhesive ability of the pure gold and alloys containing only small amounts of In was due to the chemisorbed H₂O molecules and insufficient indium oxide on the alloy surface. It was established that excellent adhesion requires an oxide with chemical affinity for 4-META to cover at least 50% of the alloy surface.