Can a bleaching toothpaste containing Blue Covarine demonstrate the same bleaching as conventional techniques? An in vitro, randomized and blinded study

OBJECTIVE: The purpose of this in vitro study was to compare the efficacy of a bleaching toothpaste containing Blue Covarine vs. conventional tooth bleaching techniques using peroxides (both in-office and at-home). MATERIAL AND METHODS: Samples were randomly distributed into five experimental groups (n=15): C - Control; BC – Bleaching toothpaste containing Blue Covarine; WBC – Bleaching toothpaste without Blue Covarine; HP35 - In-office bleaching using 35% hydrogen peroxide; and CP10 – At-home bleaching with 10% carbamide peroxide. The dental bleaching efficacy was determined by the color difference (ΔE), luminosity (ΔL), green-red axis (Δa), and blue-yellow axis (Δb). The CIELab coordinates were recorded with reflectance spectroscopy at different times: T0 - baseline, T1 – immediately after bleaching, T2 - 7 days, T3 - 14 days, and T4 - 21 days after the end of treatments. Data were analyzed by a repeated measures mixed ANOVA and post hoc Bonferroni test, with a significance level of 5%. RESULTS: No significant differences were found between the treatment groups C, BC, and WBC. The groups HP35 and CP10 showed significantly higher whitening efficacy than groups C, BC, and WBC. CONCLUSIONS: There were no significant differences in the whitening efficacy between a Blue Covarine containing toothpaste, a standard whitening toothpaste, and a control. Neither of the whitening toothpastes tested were as effective as in-office or at-home bleaching treatments.