The effect of different light-curing methods on temperature change of two types of resin-luting cements.

Objective: The purpose of this study was to investigate the temperature rise of two resin-based luting cements when photo-activated with three light-curing units. Materials and Methods: Sixty cylindrical discs (5 mm x 2 mm) from Z-250 were fabricated. The two resin-based luting cements (Choice, Bisco and Bi-fix, Vovo) were polymerized with three different light curing units (halogen light curing unit, light emitting diodes curing unit and plasma arc curing unit). A type-K-thermocouple registered the temperature rise peak in an elastomer mold (5 mm x 2.5 mm) during photo-activation. Composite resin disc was placed on top of resin luting cement discs (5 mm x O.5 mm) and curing light was passed through composite discs to cure cement specimens. Results: The temperature change data were submitted to ANOVA and Tukey's test at 5% significance level. There was statistically significant difference in temperature rise recorded for the two resin-luting cement following polymerization by different light curing units. The light emitting diodes source produced statistically highest temperatures (P < O.O5) than the other units. The plasma arc source promoted statistically the lowest (P < O.O5) temperature with both luting resins than other curing lights units. Conclusion: When LED LCU is used in patient mouth, special care should be taken to avoid any damage to the surrounding tissue from the rise in temperature.King Saud Universit