Efficacy of whitening toothpaste containing blue covarine: A double-blind controlled randomized clinical trial

This randomized clinical trial evaluated the efficacy and safety of a blue-covarine whitening toothpaste on tooth bleaching.

Seventy-five subjects with shade mean C1 or darker were randomized into three groups (n = 25): CT-conventional toothpaste, WT-whitening toothpaste, and CP10-10% carbamide peroxide. Subjects from CT and WT brushed their teeth twice/day for 2 weeks. CP10 used bleaching gel for 4 hours/night for 2 weeks. Tooth shade and CIELab parameters were measured at baseline, after the first application, 2- and 4-week. ΔE*_ab and ΔE₀₀ were calculated. Subjects' perception about tooth color appearance, tooth sensitivity (TS), and gingival irritation (GI) were also assessed.

At all evaluation periods, it was not observed differences between WT and CT considering tooth shade (P > 0.7) or CIELab parameters (P > 0.3). At 2- and 4-week, ΔE*_ab and ΔE₀₀ were higher for CP10 than WT or CT (P = 0.001). WT and CT reported major dissatisfaction with tooth color appearance than CP10 (P = 0.001). At 1- and 2-week, WT experienced GI and TS similar to CT, both lower than CP10 (P < 0.01).

There were no significant differences in the whitening efficacy between whitening and conventional toothpastes. Neither of the dentifrices was as effective as at-home bleaching.

The silica-based toothpaste containing blue covarine evaluated in this study did not give significant tooth whitening benefits over 2 weeks of use.