Color change of composites on substrates treated with 0.2% chlorhexidine

Abstract

ABSTRACT Objective To evaluate the effect of 0.2% chlorhexidine digluconate (CHX) as a pretreatment of two types of adhesive systems on color stability of composite resin restorations. Methods Forty bovine teeth were prepared (6x6x2mm) and randomly divided into 4 groups (n=10): SB - total etch adhesive (Single Bond 2, 3M ESPE); SB + CHX - dentin pretreatment with CHX (30 seconds) followed by SB application; Adh - self-etch adhesive (AdheSE, Ivoclar Vivadent); Adh + CHX - pretreatment with CHX (30 seconds) + followed by Adh application. The teeth were restored with Filtek Z350XT (3M ESPE) and photoactivated for 40 seconds. Color measurements (EasyShade, VITA) were performed following the CIE Lab scale at baseline, 1 and 3 months (distilled water/37°C). The mean color change values (?E) and coordinates (L*, a* and b*) were statistically analyzed (2-way ANOVA, repeated measures, Bonferroni, p <.05). Results Results showed that there was a reddening and yellowing of the restorative material after 3 months, differing (p <.05) from 1 month. There was no difference (p >.05) regarding the treatment with CHX. Conclusions The 0.2% CHX adhesive pretreatment did not produce greater color changes in composite resin restorations irrespective of the type of adhesive system used. However, time had significant effect on the change, regardless of the substrate treatment.