AIM:

To evaluate the effect of composite pre-heating on the microhardness of different monomer resin-based.

MATERIALS AND METHOD:

Circular specimens of methacrylate- and silorane-based composite resins pre-heated at 23, 39, and 55˚ C were carried out, and cured using a halogen light-curing unit at 650 mW/cm². After 24 h, the specimens were polished and Knoop hardness number (KHN) was measured using a microhardness tester with 50-g load for 15 s. The data were analyzed with ANOVA and Tukey’s tests (α = 0.05).

RESULTS:

Top surface presented higher KHN than bottom, methacrylate-based composite showed higher KHN compared to silorane, and pre-heating increased the KHN of the composites tested.

CONCLUSION:

Pre-heating can be used to improve the microhardness of methracrylate- and silorane-based composites.