Method: the identities of the dentifrices G1-Colgate Luminous White; G2- Close up White Now; G3- Sorriso dentifrice (no bleaching effect-placebo) were concealed by inserting its content in individual generic tubes for toothpastes, that were labeled with numbers. Thirty volunteers (10 per group) were selected according to inclusion and exclusion criteria. Tooth color values (CIELab system) were obtained with a spectrophotometer (Vita Easy Shade Compact) and tooth sensitivity values using a visual analogue scale (VAS) in baseline. Volunteers with tooth sensitivity values=zero in baseline, received randomly the blinded dentifrices tubes and were instructed to use only the supplied dentifrice and toothbrush to make the habitual oral hygiene, three times per day during four weeks. Tooth sensitivity and tooth color were assessed once per week until complete the period of four weeks. One-way analysis of variance (ANOVA) and Tukey test (alpha= .05) were used to compare ΔE (tooth color alteration) between groups. Kruskal-Wallis and Mann-Whitney tests (alpha = .05) was used to evaluate tooth sensitivity.
Result: ΔE medium values per group (tooth color alteration) showed no significant difference (p>0.05) between G1 (ΔE=5,85), G2(ΔE=5,36) and G3 (ΔE=5,27). Also, Δa, Δb, ΔL comparisons between groups showed no significant differences. There were no significant (p>0.05) increase of tooth sensitivity considering baseline values for G1, G2 or G3.
Conclusion: the bleaching and placebo dentifrices tested showed similar performance in tooth color alteration after four weeks of use. The use of bleaching dentifrices did not cause significant tooth sensitivity.