Avaliação da alteração de cor e rugosidade superficial de resinas bulk fill após escovação mecânica e envelhecimento

Abstract

The objective of this study was to evaluate, in vitro, the color stability (ΔE) and the surface roughness (Ra) of bulk fill (Filtek Bulk Fill e Tetric N-Ceram Bulk fill) and conventional (Filtek Z350XT e Filtek Bulk fill) composites, after mechanical brushing and aging. Specimens were made (n=5), with rounded bipartite matrix (8mm diameter x 4mm thickness). They were evaluated for color change (Spectrophotometer, Color Guide, BYK Gardner) and surface roughness (PROSCAN 2100 3D optical profilometer; Scantron), initially and after the tests. They were divided into 3 groups according to the tests: A-brushing (14,600 cycles, mechanical brushing machine, Elquip); B-thermocycling (5,000 cycles, 5-55°C, 30 seconds, Thermocycler, New Ethics-Scientific Equipment S.A.); C- thermocycling followed by brushing (same protocol). After all evaluations, the means were calculated and compared by means of analysis of variance (ANOVA) and Tukey's test. The level of significance was 5%. It was concluded that all resins were influenced by brushing and thermocycling. But the resin that suffered the most changes in color and roughness after mechanical brushing and thermocycling was Tetric N-Ceram Bulk fill resin.