Comparison of Whitening Dentifrices on the Effectiveness of In-office Tooth Bleaching: A Double-blind Randomized Controlled Clinical Trial

SUMMARY Objectives: To investigate the effect of whitening dentifrices on the effectiveness of in-office tooth bleaching. Methods and Materials: A double-blind randomized controlled clinical trial was performed. The participants were randomly allocated into three groups according to the different dentifrices used during this clinical trial: regular dentifrice (group C), conventional whitening dentifrice (group CW), and whitening dentifrice containing blue covarine (group CU). All participants received in-office tooth bleaching for the maxillary anterior teeth (two sessions conducted at a one-week interval). Tooth color was measured with a spectrophotometer at baseline (T1), after the first bleaching session (T2), after the second bleaching session (T3); one week after the completion of in-office bleaching (T4); and three weeks after the completion of in-office bleaching (T5). The data were statistically analyzed through repeated analysis of variance and the Tukey test (α=0.05). Results: Sixty participants completed the study (n=20 per group). At T3, group CU exhibited the lowest ΔE values (p=0.008). The ΔE values increased from T4 to T5 in the CW and CU groups, whereas a decrease in ΔE values was observed for group C. Conclusions: The use of a whitening dentifrice containing blue covarine during in-office bleaching reduced color changes. After tooth bleaching, brighter tooth colors were observed in the participants who brushed with whitening dentifrices compared to those who brushed with a regular dentifrice.