Marginal microleakage of composite resin restorations bonded by desensitizing one step self etch adhesive

Aim: The aim of this study was to investigate the effect of desensitizing agents on microleakage of composite resin restorations bonded by one step desensitized self etch adhesive. Materials and methods: Class V cavities (3 X 4 X 2 mm) were prepared on the buccal surfaces of 30 human molars, Teeth were classified into three groups according to the type of adhesive used (n = 10). Group 1: Adper Single Bond2. Group 2: l-bond. Group 3: is a control group of composite resin restoration without bonding agent. All cavities were restored with Filtek Z250 composite resin, stored in distilled water at 37°C for 24 h and thermal cycled for 500 cycles. The root apices were sealed with utility wax, and all the surfaces, except for the restorations and 1 mm from the margins, were coated with two layers of nail varnish. The teeth were immersed in a 3% methylene blue dye solution for 24 h, and then rinsed in running water, blot-dried and sectioned longitudinally through the center of restorations from the facial to lingual surface. The sections were blindly assessed for microleakage of dye penetration by two independent evaluators using a stereomicroscope at 30X magnification for both the occlusal and gingival margins. Data were collected and statistically analyzed. Results: A Mann-Whitney test demonstrated the highest significantly dye penetration rate for group 3 versus tested groups comparing the occlusal and gingival scores for each group, Wilcoxon Rank test showed significant difference for all groups. Etch and rinse adper single bond2 adhesive record a lower significant scores of dye penetration than self etch adhesive I-bond at both enamel and dentin margins. Conclusion: All adhesive systems exhibited dye penetration at both occlusal and gingival margins. Etch and rinse system is still considered a gold standard adhesive. Adper single bond2 revealed significantly less leakage compared to I-Bond.