Abstract
Introduction
To prevent the shrinkage stresses produced during polymerization, composite resins of low polymerization shrinkage were developed.
Objective
To evaluate the microtensile bond strength in class I cavities restored by acid-etching the cavosurface angle and with composite resins indicated for posterior teeth.
Material and method
48 healthy molars were selected and divided into six groups (n = 8), considering that the cavosurface enamel of three groups was etched with 35% phosphoric acid. The teeth were restored with the Clearfil SE Bond adhesive system and Filtek Z350 XT, Empress Direct, and Charisma Diamond composite resins, which were light-cured for 40 seconds. After 24 hours, the teeth were taken to a cutting machine, which produced sections in the buccolingual and mesiodistal directions. This resulted in toothpicks of 0.9×0.9 mm that were taken to the universal testing machine for the microtensile bond strength test. Statistical analysis was performed with ANOVA and Tukey’s test (p < 0.05).
Result
There was no statistically significant difference between the groups evaluated.
Conclusion
Acid-etching the cavosurface angle did not affect the performance of restorations, probably due to the adhesive system used.
Descriptors:
Composite resins; dental cavity preparation; hardness