A comparison of bond strengths of soft denture liners to polymethyl methacrylate polymerized by conventional water bath and microwave curing techniques.

This study compared the tensile bond strengths of soft lining materials polymerized by using conventional water bath methods and microwave energy. The soft lining materials used in this investigation were heat temperature vulcanizing (H.T.V.) silicon material Molloplast-B, and room temperature vulcanizing (R.T.V) acrylic material Getz Soft Oryl. The H.T.V. specimens were prepared with retention, additional retention and without retention, and the R.T.V. specimens were prepared by using bonding agent and bonding agent plus retention. All were cured by both conventional water bath and microwave energy. Results showed that the mean bond strength of H.T.V. specimens ranged from 9.6 to 13.12 kg/cm2, while the mean bond strength of R.T.V. specimens ranged from 0.36 to 1.75 kg/cm2. In both conventional and microwave groups, the specimens prepared with retention, additional retention and without retention or using bonding agent and bonding agent plus retention did not show any significant difference when they were compared separately. But the difference between conventional and microwave groups was found significant in both H.T.V. and R.T.V. specimens. It showed that conventional water bath technique is better than microwave technique.