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Effect of finishing and polishing on surface roughness of composite resins after bleaching
Bittencourt, Bruna Fortes; Gomes, Giovana Mongruel; Trentini, Felipe Auer; de Azevedo, Mônica Regina; Gomes, João Carlos & Gomes, Osnara Maria Mongruel
Abstract
Aim: To evaluate the influence of finishing and polishing techniques on the surface roughness of
two composite resins (CRs) subjected to bleaching procedure. Methods: Forty-eight CR
specimens were divided into six groups (n=8). For G1 to G3, a microhybrid CR (Opallis; FGM)
was used, and G4 to G6, received a nanohybrid CR (Brilliant NewLine; Coltène/Whaledent). All
specimens were subjected to bleaching procedure with 35% hydrogen peroxide (two 45-min
applications, with a 5-day interval). The surface roughness of all specimens was evaluated before
and after the bleaching and/or finishing/polishing (Ra parameter) by a roughness meter. After
bleaching, the groups were subjected to finishing and polishing procedures: G2 and G5 - felt discs
+ diamond pastes; and G3 and G6 - silicon rubber tips. The control groups (G1 and G4) had no
finishing or polishing treatment after bleaching. Data were analyzed by ANOVA and Tukey’s post-test,
and t test for paired samples (α=0.05). Results: bleaching treatment increased Ra values for
the nanohybrid CR specimens, but both finishing/polishing techniques were able to reduce these
values; for the microhybrid specimens, only finishing/polishing with silicon rubber tips decreased
the roughness values. Conclusions: For both microhybrid and nanohybrid CRs, the silicon
rubber tips were effective to reduce the surface roughness after bleaching procedure.
Keywords
composite resins; dental polishing; tooth bleaching
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