Evaluation of Microhardness and Microleakage of Class II Silorane-Based Composite Restorations Post-Photoactivation Silorane-Based Composite Restorations Post-Photoactivation Techniques Technique

Abstract

Objectives: The purpose of this study was to evaluate effect of additional light curing on microhardness and microleakage at cervical third of class II silorane-based composite restorations. Methods: Class II cavities were prepared on the proximal surfaces of 20 human premolars. The specimens were randomly divided into two groups of 10. In both groups, class II cavities were restored incrementally (gingival, oblique buccal and oblique lingual) with silorane-based composite (Filtek P90) and cured (group1: occlusal curing; group 2: additional curing from buccal and lingual). The samples were immersed in 0.5% fuchsine and dye penetration was recorded at the four regions of the gingival floor. Also, Vickers hardness test was performed at a distance of 1 mm above the gingival margin. Data were statistically analyzed using ANOVA after the evaluation of normal data distribution with Kolmogorov–Smirnov test at the 0.05 level of significance. Results: The two photo activation methods significantly affected the hardness (p=0.005) and microleakage (p=0.045). Additional light curing increased Vickers hardness when compared to occlusal curing. Comparison of microleakage in different areas of the first group did not show any significant difference (p=0.240) but the differences were significant between the different areas of the second group (p=0.028). Additional light curing decreased dye penetration in the all depths. Only in the H3 and M3, curing technique showed a significant effect on the results. Conclusions: Additional light curing would cause in better hardness and less microleakage. Therefore it is suggested after initial occlusal curing.