This study evaluated the influence of beverages and brushing on the surface roughness(SR) and color change(∆E) of a composite resin.For this, 120-disks(10 mm×2 mm) of composite resin(Filtek-Z250) were prepared and polished. Initials SR(Ra-μm) and color(CIELabsystem) were measured with rugosimeter and spectrophotometer; specimens were divided into four groups(red wine, soft drink, sugar cane spirit, or artificial saliva=control) and three subgroups(without brushing; brushed with Colgate or with Close-Up). Specimens were immersed in the beverage 5×/day, for 5', over 30 day, being two subgroups brushed(120 strokes/day). Color was measuredat 15th day, 30th day and after repolishment; SR at 30th day. ∆E-values were statistically different after immersion in the beverages(p<0.05). Red wine promoted the highest alteration, followed by soft drink=sugar cane spirit and finally saliva. At 30th day, specimens exhibited ∆E higher than 15th day; after repolishing, ∆E was similar to 15th day. Beverages and brushing negatively influenced the SR. Therefore, ∆E and SR can be influenced by beverages and brushing.

This study evaluated the influence of light sources and immersion media on the color stability of a nanofilled composite resin. Conventional halogen, high-power-density halogen and high-power-density light-emitting diode (LED) units were used. There were 4 immersion media: coffee, tea, Coke® and artificial saliva. A total of 180 specimens (10 mm x 2 mm) were prepared, immersed in artificial saliva for 24 h at 37±1ºC, and had their initial color measured with a spectrophotometer according to the CIELab system. Then, the specimens were immersed in the 4 media during 60 days. Data from the color change and luminosity were collected and subjected to statistical analysis by the Kruskall-Wallis test (p<0.05). For immersion time, the data were subjected to two-way ANOVA test and Fisher's test (p<0.05). High-power-density LED (∆E=1.91) promoted similar color stability of the composite resin to that of the tested halogen curing units (Jet Lite 4000 plus - ∆E=2.05; XL 3000 - ∆E=2.28). Coffee (∆E=8.40; ∆L=-5.21) showed the highest influence on color stability of the studied composite resin. There was no significant difference in color stability regardless of the light sources, and coffee was the immersion medium that promoted the highest color changes on the tested composite resin.