ABSTRACT
Introduction: Over the years, the demand for esthetic dentistry has grown dramatically and there has been a rapid developmentof new adhesive restorative materials with nanotechnology that can restore the color and characteristics of natural tooth. Topolymerize these materials, light-curing dental materials extensively used are quartz-tungsten-halogen (QTH) and light-emittingdiode (LED)-curing units. Literature search revealed that depth of cure and flexural strength are the most important propertiesof composite resin materials, relevant to the clinical technique of incremental packing and curing.Purpose: The objectives of the present study were to evaluate and compare the depth of cure and flexural strength of ananohybrid composite resin.Materials and Methods: Two light-curing units were selected for this study: QTH (Bonart, Unicorn) and LED (Ivoclar Vivadent,Bluephase® N). The depth of cure was evaluated with scraping technique using digital caliper and flexural strength was evaluatedusing universal testing machine with a crosshead speed of 1 mm/min.Results: Descriptive statistics was employed to measure the mean and standard deviation of the depth of cure and flexuralstrength. Unpaired “t”-test was used to compare the study variables. Statistical significance was fixed at ≤0.05 and LED-curingunit showed significantly greater depth of cure and flexural strength when compared to QTH curing unit.Conclusion: Curing effectiveness of resin composite is dependent on the light-curing unit.