Efficacy of an automatic electric toothbrush with nylon bristles in dental plaque removal: a cross-over randomized controlled trial

Objectives The objective of this single-use, five-treatment, five-period, cross-over randomized controlled trial (RCT) was to compare the efficacy in dental plaque removal of a new Y-shaped automatic electric toothbrush (Y-brush) compared to a U-shaped automatic electric toothbrush (U-brush), a manual toothbrushing procedure (for 45 and 120 s), and no brushing (negative control). Materials and methods Eligible participants were volunteer students randomized to the treatments in the five periods of the study. The primary outcome measure was the reduction in full-mouth plaque score (FMPS) after brushing while the secondary outcome variable was a visual analogic scale (VAS) on subjective clean mouth sensation. Mixed models were performed for difference in FMPS and VAS. Results After brushing procedures, manual toothbrushing (120 s) showed a statistically significant reduction in FMPS than Y-brush (difference 36.9; 95%CI 29.6 to 44.1, p < 0.0001), U-brush (difference 42.3; 95%CI 35.1 to 49.6, p < 0.0001), manual brushing (45 s) (difference 13.8; 95%CI 6.5 to 21.1, p < 0.0001), and No brushing (difference 46.6; 95%CI 39.3 to 53.9, p < 0.0001). Y-brush was significantly more effective than No brushing (difference 9.8; 95%CI 2.5 to 17.0, p = 0.0030), while there was no significant difference compared to U- brush. Similar results were obtained for the differences in the Clean Mouth VAS. Conclusions Y-brush was significantly more effective than no brushing (negative control) in removing dental plaque. When compared to manual toothbrushing for both 45 and 120 s, however, Y-brush was less effective in dental plaque removal. Clinical relevanceModified design of automatic toothbrushing devices could improve plaque reduction, especially in patients with intellectual disabilities or motor difficulties.