The effect of using different rinsing angles on the micro-tensile bond strength of the sealant to the etched enamel

BACKGROUND AND OBJECTIVES: Attempts to enhance bond strength of the sealant have been among the most important sides of dental research. The purpose of the present study was to evaluate the effect of using different rinsing angles on the micro-tensile bond strength of the sealant to the etched enamel. MATERIALS AND METHODS: Sixty first-premolars were randomly assigned to six groups based on the rinsing angle applied (15°, 30°, 45°, 60°, 75° and 90°). Following etching and rinsing, a 4-mm height build-up of sealant material was created. Bonded specimens were sectioned into sticks (1 mm × 1 mm), which were subjected to micro-tensile bond strength, testing at a cross head speed of 0.5 mm/min. STATISTICAL ANALYSIS USED: The data were analyzed by Kolmogorov-Smirnov and post-hoc Tukey test. RESULTS: The tensile bond strength in specimens rinsed at 90° were statistically higher compared to those rinsed at 15° and 30° (P < 0.05) and increasing the angle from 15° to 90° was correlated with a reduction in the number of specimens with adhesive failures. CONCLUSIONS: Rinsing the conditioned enamel surface at 90° may improve the bond strength and retention of the sealant.