10% carbamide peroxide and Plaque and Gingival Index scores

Methods: Data from a series of randomized double-blind clinical trials used to guide development of a whitener were analyzed. Eight agents containing 10% CP were included. Plaque and Gingival Indices of Loe & Silness were used to score plaque volume and gingival inflammation respectively. 19 to 22 people were in each group for a total of 161. Evaluations were performed at baseline (E1), after one (E2) and two weeks (E3) of active bleaching and four weeks following the cessation of bleaching (E4). The data for the active agents were examined to determine if there were significant differences between agents. As there were not, the data were analyzed in the aggregate.

Results: There were no significant differences in PI or GI scores for any of the agents (RM ANOVA; p = 0.68 & 0.22). Median PI scores at each evaluation were: 0.13 (E1); 0.03 (E2); 0.00 (E3); and 0.13 (E4). Median GI scores were: 0.13 (E1); 0.13 (E2); 0.09 (E3); and 0.15 (E4). PI and GI scores were significantly associated with the evaluation periods (RM ANOVA on ranks; p = 0.001 & 0.009). Relative to E1, PI scores were significantly lower at E2 and E3, but not E4 (p < 0.05). There were no significant differences between E1 and any other evaluation for GI scores (p > 0.05). Dunn's method used for all post-hoc tests.

Conclusion: In this study, the use of 10% carbamide peroxide over a two week period was associated with a significant reduction in plaque volume and gingival inflammation. At four weeks post-bleaching scores had returned to baseline levels. Supported by Ultradent Products, Inc.