Effect of surface sealant on the color stability of composite resin restorations.

This study investigated the effect of sealant application on the color stability of composite resin restorations. Cavities in bovine incisors were restored with composite resin (Opallis; FGM) and the teeth were assigned to 4 groups (n=10). A sealant (Fill Glaze; Vigodent) was applied over the restorations of 2 groups. Baseline color measurements based on the CIEL*a*b* system were carried out using a spectrophotometer. Half the number of specimens was immersed in distilled water, and half was immersed in coffee 4 h/day. Color measurements were repeated after 1 h, 24 h, 7 days and 3 months. Data for each immersion solution were separately subjected to a two-way repeated measures ANOVA and Tukey's test (α=0.05). For the group without sealant immersed in water, no significant differences were observed among the periods (p ≥ 0.138), but the color was different compared with baseline (p<0.001). For the group with sealant application, the periods baseline, 1 h and 3 months presented similar results (p ≥ 0.924). For groups immersed in coffee, when the sealant was not used, no significant differences were detected between the baseline and the periods 1 h and 24 h (p ≥ 0.499), but the color changed significantly thereafter (p ≤ 0.003). In the group with sealant, significant differences were detected for all periods compared with each other (p<0.001). In conclusion, application of sealant dramatically increased the staining of the restorations exposed to coffee.