Iranian Dental Association Journal of Iranian Dental Association 3060-8201 25 3 2013 07 01 Microleakage Evaluation of Silorane-Based Composites Versus Low Shirinkage Methacrylate-Based Composites 147 154 EN Hamid Kermanshah Esmaeil Yassini Raziyeh Hoseinifar Mansoreh Mirzaei Ayub Pahlavan Masomeh Hasani Tabatabaie Sakineh Arami Journal Article 2013 07 22 2013 11 18 Background and Aim : Determining the best restorative material to decrease microleakage in class V restorations is of great importance in operative dentistry. The aim of this in-vitro study was to evaluate the microleakage of silorane-based composites compared to low shrinkage methacrylate-based composites in class V restorations. Materials and Methods : In this in vitro study, class V cavities were prepared on the buccal and lingual surfaces of 24 human premolars and molars (48 cavities). The specimens were divided into four groups of 6(12 cavities) as follows: group 1 ( LS System Adhesive, Primer & Bond + Filtek P90), group 2 ( Kalore-GC+ Clearfil SE bond ), group 3 ( Clearfil SE bond + Grandio) and group4 ( Clearfil SE bond + Aelite LS Posterior) . All the specimens were thermocycled for 2000 cycles (5-50oC). The teeth were then immersed in 0.5% basic fuchsin dye for 24 hours at 370C, sectioned and observed under stereomicroscope. Data were analyzed using Kruskal-Wallis and Wilcoxon tests at a P<0.05 level of significance . Results : There were no significant differences in microleakage among the four groups at the occlusal margin (P>0.05). But, there were statistically significant differences in microleakage between Silorane and Aelite at the gingival margin (P<0.05). Statistically significant differences were also found in microleakage between occlusal and gingival margins (except for Kalore and Silorane) (P>0.05 ) Conclusion : Silorane was not superior to the conventional low shrinkage methacrylate-based composites except for Aelite in terms of microleakage .