Methods: Two single-brushing studies and a 12-week multiple-use study were re-analyzed separately on lingual and buccal surfaces based on statistically significant brush effects for whole mouth plaque. All three studies compared an oscillating rotating brush with a small round brush head, Oral-B® Triumph® with FlossAction™ brush head (OB), versus a sonic brush with a standard-size brush head, Sonicare® FlexCare with Proresults standard brush head (FC). The single-brushing studies were 2-treatment, 4-period crossover designs measuring overnight and post-brushing plaque; study 1 used Rustogi Modification of the Navy Plaque Index (RMNPI) and study 2 used Turesky Modified Quigley Hein Plaque Index (TMQHI). Plaque removal was compared using mixed modeling. Study 3 compared brushes for post-brushing RMNPI plaque scores at 6- and 12-weeks, adjusting for baseline plaque level using analysis of covariance.
Results: In studies 1 and 2, the OB brush had statistically larger plaque removal scores than FC for each of the lingual and buccal surfaces; % mean removal differences between brushes of 33.2% for lingual and 12.8% for buccal in study 1 (p<0.001) and 18.3% for lingual and 7.8% for buccal in study 2 (p≤0.044). Study 3 showed the OB brush group had statistically lower post-brushing plaque levels than the FC group at 6 and 12 weeks for each of the lingual and buccal surfaces; % mean post-brushing differences between brushes of 32.2% for lingual and 25.5% for buccal at 6 weeks (p≤0.008) and 34.4% for lingual and 31.3% for buccal at 12 weeks (p<0.001).
Conclusions: An oscillating rotating brush and small round brush head demonstrated greater buccal and lingual plaque effectiveness relative to a sonic brush and standard brush head in single-use and long-term research, with increasing improvement on lingual surfaces.
Keywords: Biostatistics, Clinical trials, Plaque, Surfaces and Toothbrushes