Efeito do resveratrol na resistência de união entre esmalte dental clareado e resina composta

Abstract

The present study aimed to evaluate the effect of resveratrol on the bond strength between bleached dental enamel and composite resin. Thirty bovine teeth were divided into 5 groups (n=6): without bleaching or antioxidant (Ctrl-control); lightening and without antioxidant (Res0); and whitening and application of 10% resveratrol for 5, 10 or 15 min (Res5; Res10; Res15). 35% hydrogen peroxide was applied for 45 min and removed by washing with air-water jets and drying. Resveratrol was applied to enamel after whitening for the time designated for the experimental group and washed with air-water jets. After etching, a layer of universal adhesive (Ambar®, FGM, Joinville, SC, Brazil) was applied and photoactivated. Composite resin restorations with 1 cm² of adhesive area and 3 mm in height were made in increments inside the silicone matrix. The samples were sectioned in a cutting machine under water cooling (250rpm) obtaining specimens in the form of sticks, with 6 mm in length and 1mm² in cross-sectional area. The specimens were then submitted to the microtensile test (0.5 mm/min) in a universal testing machine. The force (N) at the moment of failure was recorded and the bond strength (σt) calculated (MPa). Data were analyzed by Kruskal-Wallis at 5%. The results demonstrate that tooth bleaching negatively affects the bond between the composite resin and the enamel surface. The application of 10% resveratrol extract for 10 and 15 min resulted in bond strength values similar to the control group.