Influence of LED and Halogen Curing Lights on the Flexural Strength and Elastic Modulus of Nano-Filled Dental Composites

Abstract

Objective: The aim of the present study was to compare the flexural strength and elastic modulus of nanofilled, hybrid, and microhybrid composite resin materials cured with either QTH or LED curing lights. Methods: rectangular bar-shaped specimens (25mm × 2mm × 2mm; n=10 per group) of five dental resin-based composites were irradiated with either light emitting diodes (LEDs) or quartz-tungsten-halogen (QTH) lights. Three point flexural strength and elastic modulus were measured. Two way analysis of variance were made at p=0.05. Independent sample T-test was also performed. Results: The mean flexural strength values of Filtek Supreme and Filtek Z250 cured with LED were significantly higher than those cured with QTH (p= 0.007, p=0.037 respectively). While the mean elastic modulus values of Filtek Supreme and Tetric Evo Ceram cured with LED were significantly higher than those cured with QTH (p=0.001, p=0.013respectively). However, there was no statistically significant difference in the mean flexural strength and modulus values of the other test materials cured with either QTH or LED. Conclusion: the flexural strength and elastic modulus values of Filtek Supreme, Filtek Z250, and Tetric Evo Ceram cured with LED were higher than those cured with QTH light.