Mitra Tabari - Assistant Professor, Dental Material Research Center, School of Dentistry, Babol University of Medical Sciences, Babol, Iran
Samane Gharekhani - Assistant Professor, Department of Pediatrics, School of Dentistry, Babol University of Medical Sciences, Babol, Iran
Behnaz Esmaeili - Assistant Professor, Department of Operative Dentistry, School of Dentistry, Babol University of Medical Sciences, Babol, Iran
Arash Poorsattar Bejeh Mir - Researcher Dentist, Dental Material Research Center, School of Dentistry, Babol University of Medical Sciences, Babol, Iran

Introduction: In recent dentin adhesive systems etching of enamel/dentin are achieved simultaneously. The objective was to evaluate the microleakage of composite restorations using Single Bond2 (5th generation), Clearfil S3 Bond and G Bond (7th generation). Methods: Class V cavities were prepared on  45 extracted intact premolars with gingival margins at the cementoenamel junction and they were randomly divided into 3 groups (n=15) based on the type of adhesives: Single Bond2 (5th generation), Clearfil S3 Bond and G Bond (7th generation). After applying the adhesives, the cavities were filled with Z250 composite resin. The occlusal and gingival microleakage was evaluated using 2% basic fuchsin staining technique. Data were analyzed using Kruskal-Wallis and Bonferroni corrected Mann-Whitney U tests. Results: The mean rank of occlusal microleakage exhibited significant differences by comparison of G Bond, Clearfil S3 Bond and Single Bond2 (21.07, 30.67) and 17.27, respectively) (P=0.005). There was a significant difference in gingival microleakage of different bonding agents (34.40, 17.83 and 16.77 for G Bond, Clearfil S3 Bond and Single Bond2, respectively) (P<0.001). There was a significant difference in occlusal microleakage of Clearfil S3 Bond and Single Bond2 (P= 0.003), but no significant difference was found between Clearfil S3 Bond and G Bond (P=0.025). No significant difference was observed between occlusal microleakage by G Bond and Single Bond2 (P=0.238). The difference in gingival microleakage was significant by G Bond compare with Single Bond2 and Clearfil S3 Bond (P<0.001and P<0.001, respectively). Conclusion: The microleakage of class V composite restorations in permanent teeth using the Single Bond2 was lower than that with the use of G Bond in gingival margins. The sealing ability with Single Bond2 was superior to Clearfil S3 Bond in occlusal margin but they were equally effective at gingival margin.  

words: Bonding agent, Composite Resin, Dentin, enamel, Microleakage