[Bonding durability of various adhesion systems of dental alloy in aciditic solution]

Previous studies found that the adhesive resin provided strong adhesion to alloys. Also, the bond durability was improved by oxidation of alloys. In oral, many aciditic substances exist. However, the oxides yielded by oxidation are unstable in aciditic environment. Thereupon, the adhesive resin systems should be studied in aciditic environment. In this study, half of the alloy disks were air-brushed with alumina and the remaining half were polished with #600 emery. They were then ion-coated. One third of the disks were with Cu oxide another one third were Cu.Sn oxide, and remaining were Sn oxide. The handle was affixed by the 4-META resin. For reference, Co-Cr specimen oxidized ultrasonically was fabricated. Completed specimens emery polished were stored in lactic acid at 37 degrees C for 3 months, and sand-blasted were for 6 months. Then the tensile strength was measured. In 0.002% solution, initial bond strength of all the specimens was maintained after immersion. After 1.0% immersion, bond strength of Cu oxide coating specimen polished with emery decreased rapidly. Bond strength of Cu.Sn oxide and Sn oxide coated specimens decreased slowly. Sand-blasted specimens showed higher durability than emery polished. Co-Cr alloy specimen showed the highest durability, and 260 kgf/cm2 was maintained after 6 months in 2.0%.