Tehran University of Medical Sciences Frontiers in Dentistry 2676-296X 11 2 2014 04 15 150 60 Maryam Khoroushi Associate Professor, Dental Materials Research Center and Department of of Operative Dentistry, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran. Mojgan Rafizadeh Torabinejad Dental Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran. Pouran Samimi Associate Professor, Dental Materials Research Center and Department of of Operative Dentistry, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran. 2015 10 16 Ethanol wet-bonding (EWB) technique has been stated to decrease degradation of resin-dentin bond. This study evaluated the effect of two EWB techniques on composite resin-to-enamel bond strength.Silicon carbide papers were used to produce flat enamel surfaces on the buccal faces of forty-five molars. OptiBond FL (OFL) adhesive was applied on enamel surfaces in three groups of 15 namely: Enamel surface and OFL (control);Protocol 1 of the EWB technique: absolute ethanol was applied to water-saturated acid-etched enamel surfaces for 1 minute before the application of ethanol-solvated hydrophobic adhesive resin of OFL 3 times;Protocol 2: progressive ethanol replacement; water was gradually removed from the enamel matrix using ascending ethanol concentrations before OFL application. Composite build-ups were made and the specimens were stored for 24 hours at 37°C and 100% relative humidity. Shear bond strength test was performed using a universal testing machine at 1 mm/min crosshead speed. Fracture patterns were evaluated microscopically. Data were analyzed with one-way ANOVA and Fisher's exact test (α=0.05).There were no significant differences in bond strength between the groups (P=0.73). However, regarding failure patterns, the highest cohesive enamel fractures were recorded in groups 2 and 3.In this study, although both methods of EWB did not influence immediate bond strength of composite resin to enamel, the majority of failure patterns occurred cohesively in enamel. https://fid.tums.ac.ir/index.php/fid/article/view/531 https://fid.tums.ac.ir/index.php/fid/article/download/531/507