The effects of oscillating-rotating electric toothbrushes on plaque and gingival health: A meta-analysis

To compare the effects of oscillating-rotating (O-R), sonic (side-to-side), and manual toothbrushes on plaque and gingival health after multiple uses in studies up to 3 months.

A meta-analysis was conducted on randomized clinical trials (RCTs) up to 3 months in duration to evaluate O-R electric toothbrush effectiveness regarding gingivitis reduction and plaque removal versus sonic and/or manual toothbrushes. To ensure access to subject-level data, this meta-analysis was limited to RCTs involving O-R toothbrushes from a single manufacturer conducted from 2007 to 2017 for which subject-level data were available and that satisfied criteria of duration, parallel design, examiner-graded, etc. For gingivitis studies, a one-step individual subject meta-analysis was used to assess direct and indirect treatment differences and to identify any subject-level covariates modifying treatment effects. In the two-step meta-analysis, individual participant data were first analyzed in each study independently using the last timepoint (up to 3 months), producing aggregate data for each study. Then forest plots were produced using these aggregate data with random-effects models. For plaque studies, the efficacy variables were standardized so direct comparisons could be generated using the 2-step meta-analysis. Network meta-analysis was performed to assess the indirect plaque comparisons.

16 parallel group RCTs with 2,145 subjects were identified assessing gingivitis via number of bleeding sites. In five and 11 gingivitis studies assessing O-R brushes versus manual and sonic brushes, respectively, a change in the average number of bleeding sites of -8.9 ( 95% CI: -15.9, -1.9) and -3.1 (95% CI: -3.8, -2.4) was observed (P ≤ 0.008). These reductions equate to a 50% and 28% bleeding benefit for O-R technology versus the respective controls. The sonic brush bleeding change versus manual was -5.9 (P = 0.062), a 34% bleeding benefit. Utilizing individual bleeding scores, subjects with localized or generalized gingivitis (≥ 10% bleeding sites) had 7.4 times better odds of transitioning to generally healthy (< 10% bleeding sites) after using an O-R brush versus manual. 20 parallel design RCTs with 2,551 subjects assessed plaque (TMQHI, RMNPI). In eight and 12 plaque RCTs assessing an O-R brush versus manual and sonic brushes, respectively, standardized changes in average plaque scores of -1.51 (95% CI: -2.17, -0.85) and -0.55 (95% CI: -0.82, -0.28) were observed (P< 0.001). These plaque reductions by O-R equate to a relative 20% and 4% greater benefit, respectively. The change for sonic versus manual was -0.93 ( 95% CI:-1.48, -0.38); (P < 0.001) which equates to a 12% plaque benefit.

This subject-level meta-analysis of studies up to 3 months provides sound evidence supporting recommendations for patients with various degrees of gingival bleeding to use oscillating-rotating electric toothbrushes over manual and sonic toothbrushes to improve plaque control and gingival health.