RESUMO
PURPOSE: To evaluate the effectiveness of five whitening toothpastes applied three times a day for 4 weeks. METHODS: 25 human extracted teeth were selected. Two peroxide-based dental bleaching pastes (professionally delivered): Enawhite 2.0 (En), Whitekin (Wk); and three over the counter whitening toothpastes: Opalescence whitening toothpaste (Op), Colgate max White expert White (Cg) Premium activated charcoal (Cr) were used. Teeth were brushed for 4 weeks, three times a day. Color was measured with a spectrophotometer according to the CIELab system. ΔEab, W* and ΔE00 values were calculated at baseline, at the end of the treatment, and 1 week after the end of treatment. Data analysis was performed using a generalized estimating equations model, evaluating the effect of treatment, time and interaction (P< 0.05). RESULTS: ΔEab values ranged from 5.01 for En to 3.22 for Wk after the 4-week treatment period. One week after the end of treatment, ΔEab ranged from 5.91 for Cr to 3.62 for Op (P> 0.05 between groups). The closest to pure white (W* differences between baseline and after 1 week from the end of treatment) was for En and Wk. ΔE00 values after 4 weeks of treatment ranged from 3.23 for En to 1.79 for Wk. One week after the end of treatment, the ΔE00 ranges were between 3.31 for Cr to 2.03 for Op (P> 0.05 between groups). CLINICAL SIGNIFICANCE: All the evaluated whitening toothpastes improved dental color values higher than those perceptible and acceptable at the 50:50 threshold.