Effect of carbamide peroxide bleaching agent on the surface roughness and gloss of a pressable ceramic.

Objective: This study evaluated the influence of carbamide peroxide, 10% and 16%, on the surface roughness and gloss of a pressable ceramic.

Materials And Methods: Carbamide peroxide (10% or 16%) was applied for 4 hours or 3 hours per day for 14 days, respectively, in pressable ceramic discs (14 mm × 2 mm). Specimens were stored in distilled water at 37°C.

Surface roughness of composite resins subjected to hydrochloric acid.

The purpose of this study was to determine the influence of hydrochloric acid on surface roughness of composite resins subjected to brushing. Sixty samples measuring 2 mm thick x 6 mm diameter were prepared and used as experimental units. The study presented a 3x2 factorial design, in which the factors were composite resin (n=20), at 3 levels: microhybrid composite (Z100), nanofilled composite (FiltekTM Supreme), nanohybrid composite (Ice), and acid challenge (n=10) at 2 levels: absence and presence.