Efficacy of light curing unit prototype on surface hardness of resin composite as a function of tilt angle
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Abstract
Purpose : To evaluate the efficacy of light curing unit (LCU) prototype and to compare microhardness values of resin composite at different tilt angles.
Materials and methods : Ninety composite resin specimens were prepared using plastic molds (6.0 mm internal diameter and 2 mm. depth) and divided into nine experimental groups (n=10) : Three LED light curing units (Celalux2, Bluephase and SangSeeFah) and three different tilt angles (α = 90°, 80°, 70°). After 24 h, Vicker-hardness measurement was made on the top and bottom surfaces of the specimen. The values were analyzed by two-way ANOVA and Tukey’s test (P < 0.05).
Results : The microhardness values showed no significant differences between different tilt angles while using SangSeeFah and Bluephase. By increasing the tilt angle of Celalux2 the top microhardness showed significantly decreased. and Celalux2 had the lowest hardness compared to all LCU at all angles.
Conclusion : The tilt angle of Celalux2 had an effect on microhardness of resin composite. Different light curing units gave the different levels of resin composite polymerization.
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References
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