Efficacy of non-hydrogen peroxide mouthrinses on tooth whitening: An in vitro study.

OBJECTIVES: To evaluate the tooth whitening efficacy of non-hydrogen peroxide containing mouthrinses. METHODS: Forty incisors were randomly assigned into four groups. Four whitening mouthrinses, Oral-B 3D White Luxe/Procter & Gamble (WL), Listerine Advanced White/Johnson & Johnson (AW), Colgate Max White/Colgate (MW), and iWhite Whitening Mouthwash/Sylphar (iW), were used over a four-week period. Color changes of L*, a*, b*, DeltaE*(ab) , and DeltaE(00) , were recorded by a digital spectrophotometer (Spectroshade Micro/Mht), at baseline and intermediate week-intervals. Data were statistically analyzed using repeated measures ANOVA at alpha = 0.05. RESULTS: The first-week mean change of L* was 0.76 and significantly different from the baseline for all solutions, without any further changes. Correspondingly, a* decreased by -0.36, while b* increased by 0.48, contributing to a color change of 1.15 DeltaE*(ab) or 0.91 DeltaE(00) . No differences were found among the solutions in respect to color-parameter changes (p > 0.05). Differences among time intervals were significant (p < 0.05) and mainly observed between the baseline and the following week-measurements. There was no statistically significant time-solution interaction (p > 0.05). CONCLUSIONS: Non-hydrogen peroxide whitening mouthrinses, slightly contribute to tooth whitening, by removing superficial staining, without any further tooth bleaching effect. CLINICAL SIGNIFICANCE: Non-hydrogen peroxide containing whitening mouthrinses, despite having a quick initial action, reach their ceiling relatively soon. Their effectiveness is barely perceptible and definitely inferior to other professional tooth bleaching methods. Thus, they can only be considered as a supplementary way of keeping teeth whiter, mainly by preventing recurrent tooth discoloration.