Comparative Plaque Removal Efficacy of Three Manual Toothbrushes

The purpose of this study was to determine the safety and plaque-reducing effectiveness of a newly designed manual toothbrush compared to that of a leading marketed toothbrush and a reference standard manual toothbrush control.

This examiner-blind, randomized, single-use study used a cross-over design. Sixty-eight qualifying male and female subjects were randomly assigned either an Arm & Hammer™ Truly Radiant™ Deep Clean manual toothbrush (TR), a Colgate® Extra Clean manual toothbrush (C), or an ADA reference standard manual toothbrush (SM) according to one of three computer-generated sequences. Following instruction in the use of their assigned brush, subjects brushed at home with a standard fluoride toothpaste twice daily for two minutes during a one-week familiarization period. At the end of this period, the subjects returned to the study site after refraining from oral hygiene for 12-16 hours and from eating and drinking for four hours. Plaque was disclosed and scored using the Rustogi Modification of the Navy Plaque Index (RMNPI). Subjects brushed under supervision with their assigned toothbrush for two minutes in a room without mirrors and apart from the dental examiner, after which plaque was disclosed and rescored. They were then given one of the alternate toothbrushes according to their assigned sequence, and the familiarization routine and evaluations were repeated until each of the subjects used each of the three brushes. Within-treatment and between-treatment whole mouth RMNPI scores and scores at each of twelve subsets of sites were analyzed using paired t-tests and appropriate ANCOVA models, respectively.

Within-group analyses showed that all three toothbrushes produced statistically significant reductions from the pre-brushing baseline in whole mouth RMNPI scores (p < 0.0001), with respective reductions of 68.2%, 58.3%, and 48.5% for TR, C, and SM. Between-group analyses showed that TR was significantly more effective (p < 0.0001) than C and SM with 16.4% and 40.3% greater reductions in whole mouth scores, respectively. TR also produced statistically significant greater reductions (p < 0.0001) than the other two manual brushes at each of the twelve subsets of sites examined, with the greatest differences at the lingual and gingival sites, especially sites presenting difficulty in access, such as those in the posterior lingual gingival region.

While all three manual toothbrushes produced significant supragingival plaque reductions with a single use, the Truly Radiant Deep Clean brush was significantly more effective than the Colgate Extra Clean and ADA manual brushes in reducing wholemouth plaque, as well as plaque at all subsets of sites analyzed including difficult-to-reach areas.