THE EFFECTS OF THERMAL CYCLING ON THE BOND STRENGTH OF SELF-CURING RESIN

Cho, Hye Won; Ha, Jum In

Abstract

The purpose of this study was to evaluate the effects of two metal adhesive primers on the shear bond strengths of self-curing resin to Ni-Cr alloy and the effects of 1000 thermal cycling on the durability of the bond. The two selected metal adhesive primers were Metal Primer II(G-C corp., Japan) and MR Bond(Tokuyama corp., Japan) and to treatment groups were used as control. All specimens were divided into two groups according to thermal cycling. In the group without thermal cycling. the specimens were stored in water for 24 hours. In the group with thermal cycling, the specimens were thermocycled 1000 times at temperature of 5degrees C and 55degrees C. Shear bond strengths were measured using the Universal testing machine(Zwick 145641, Germany) with a crosshead speed of 0.5 mm/min. The results were as follows: 1. MR Bond significantly improved the shear bond strength of resin to Ni-Cr alloy before and after thermal cycling. 2. There were no difference in the shear bond strength of resin to Ni-Cr alloy between Metal Primer II treated group and no treatmet group. 3. Regardless of the type and the use of adhesive primers, there were tendency of decrease in shear bond strength with 1000 thermal cycling.