Effect of triclosan/copolymer-containing toothpaste on the association between plaque and gingival bleeding: a randomized controlled clinical trial.

Aim: To study longitudinal associations between plaque and gingival bleeding and multilevel variance/covariance structures after introducing triclosan-containing toothpaste. Material and Methods: A 10-week, randomized, two-arm, double-masked, controlled clinical trial was conducted in 34 healthy, non-smoking females with plaque-induced gingivitis. Clinical periodontal examinations were repeated every other week. At week 4, test toothpaste containing 0.24% sodium monofluorophosphate, 0.3% triclosan, and 2% polyvinyl–methyl ether maleic acid; or control toothpaste containing 0.76% sodium monofluorophosphate and 0.1% sodium fluoride, were randomly distributed. Results: Multivariate multilevel models indicated that, after introducing experimental toothpastes, subject random error was reduced from 0.6 to below 0.2. The odds ratio (OR) of bleeding on probing (BOP) was about 30% less in the test than in the control group (p<0.01). At the end of the experiment, ORs for BOP and plaque index scores 1–3 (reference 0) were 2.1–2.4 in the control group, but 1.1–1.9 in the test group (p<0.05). No effects on plaque levels and calculus were observed. Conclusions: Multivariate multilevel modelling allows the study of fixed and random effects of experimental toothpastes on gingival inflammation in small sample. Triclosan appears to attenuate the causal association between supragingival plaque and gingival bleeding in gingivitis.