A 1-week study was conducted to compare the
tooth whitening efficacy of two
carbamide peroxide-based products (one containing 5%
carbamide peroxide and one containing 10%
carbamide peroxide). In addition, the perception of transient tooth
hypersensitivity associated with the use of these products was subjectively evaluated. Sixty participants took part in a double-blind, randomized, parallel clinical study. Change in tooth color was measured by chroma meter and Vita shade guide at the initiation of the study and after 7 days of product use. Color change (delta E) was calculated using the color-difference equation established by the Commission Internationale de L'Eclairage. Data concerning dental
hypersensitivity was assessed by subjective panelist questionnaires administered after the day 7 recall examination. Results of the whitening data showed that there was no significant difference between the two products. After 1 week, the mean delta E for the product containing 5%
carbamide peroxide was 4.43 +/- 1.89 and the mean delta E for the product containing 10%
carbamide peroxide was 4.05 +/- 1.84. However, the subjective data collected on tooth
hypersensitivity showed that the product containing 5%
carbamide peroxide was associated with less discomfort. Of the group using the 5%
carbamide peroxide product, 20% reported transient sensitivity of their teeth after product use for 1 week compared with 53% of the group using the product with 10%
carbamide peroxide. Statistical analysis using a 2-tailed t test showed significant differences between the two groups (P < .05). The data suggest that these products are clinically equivalent for
tooth whitening; however, the product containing 5%
carbamide peroxide was associated with less tooth
hypersensitivity after 1 week of application.