The effect of wrapping of light-cure tips on the cure of composite resin

Abstract

Abstract Aim: Dental curing lights are vulnerable to contamination during routine intra-oral use. The purpose of this study was to evaluate the effect of wrapping light-cure tips on the hardness of cured composite resin. Settings and Design: Two types of barriers were used, which are the commercially available cellophane wraps and the disposable light-cure sleeves. A new light-cure unit used with a standard light-cure tip fixed at distance of 0.5 mm from the specimens. Materials and Methods: Sixty molds of 8 mm diameter and 2 mm depth filled with same type and shade of composite resin; 20 specimens cured without wrapping the tips, and 20 used for each wrapping method with new barrier was placed for each. The light-cure intensity and the Knoop hardness value were recorded. Statistical Analysis: Kruskal-Wallis test was used to analyze the statistical differences between the groups. Pearson′s correlation analysis was used to determine the correlation between light intensity and Knoop hardness values. Results: The results of this study showed that there were significant differences in the light intensity among the groups. However, there were no significant differences in the Knoop hardness values among the 3 groups. The cellophane-wrapped around the light-cure tips is appeared to cause the least reduction of hardness from the non-wrapped tip. Conclusions: The effect of the barriers on the hardness of composite resin was small and probably clinically insignificant. The light intensity output was above the acceptable curing levels using any of the two barriers. The use of non-opaque barriers with the light-cure tips is recommended to prevent cross contamination.