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 ll(G-C corp., Japan) and MR Bond(Tokuyama corp., Japan) and no 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 51´, and 551C. 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 11 treated group and no treatment group.
3) Rega Bless of the type and the use of adhesive primers, there were tendency of decrease in shear bond strength with 1000 thermal cycling.
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