Comparison of the Whitening Effect of Two 10% Bleaching Products

Objectives: To evaluate the efficacy of two different 10% carbamide peroxide bleaching products just after treatment and after a 6-month follow-up period. Methods: Two ten percent carbamide peroxide products (Opalescence PF and Nite White ACP) were applied nightly for 14 days, according to the manufacturer's instructions. The color of teeth 11 and 21 of seventeen subjects (x2) having A2 or darker teeth were measured with a spectrophotometer (L*; a*; b*) before treatment, just after treatment (14 days), and 6 months after treatment. Subjects were instructed to take note of any tooth sensitivity. Results: Highly significant differences (p < 0.01; Wilcoxon Signed Rank Sum Test) were found for all three components (L*, a* and b*) for both products between base-line values and the values obtained after treatment (14 days later) as well as between base-line and after 6 months (Wilcoxon Signed Rank Sum Test). However, no significant differences (p>0.05) were found between 14 days and 180 days for the L*, a*, b* and ΔE*ab for Opalescence but for Nite White significant differences (p<0.05) (deterioration in color) in L*, a*, b* and ΔE*ab were found. When comparing the two products no significant differences (p>0.05) in the L*, b* and ΔE*ab were found just after treatment (after 14 days) as well as after 180 days. The L* value decreased (less white/bright) with 8.2% for Opalescence but with 46.3% for Nite White from just after treatment to 6 months later. The b* value also decreased (more yellow) with 20.4% for Opalescence but with 42% for Nite White during the 6 month period after treatment. Conclusions: Both products whitened teeth equally well. In general the deterioration after 6 months was more for Nite White than for Opalescence. This study was supported by the South African Dental Association's DDF fund.