Effect of a powered and a manual toothbrush in subjects susceptible to gingival recession: A 36-month randomized controlled clinical study.

Objective: The objective of this long-term clinical study was to evaluate the influence of a newly developed powered toothbrush (PT) on the size and number of pre-existing gingival recessions (GR) in comparison to a manual toothbrush (MT).

Methods: This was a prospective, single-blind, parallel-group, randomized controlled clinical study. Participants without periodontitis, but with at least two teeth (index teeth) showing GR ≥2 mm were randomized to brush either twice daily with a MT or with a PT with a linear magnetic drive causing the round brush head to produce gentle micro vibrations along with oscillating-rotating movements. Primary outcome parameter was the mean change of GR at the index teeth over 36 months.

Results: Totally 87 out of 92 participants completed the study (MT/PT: n = 42/n = 45). At the 36-month evaluation the mean (standard deviation) change of GR at index teeth differed significantly between MT 0.17 (0.77) and PT -0.10 (0.63) (p = 0.013). Furthermore, the amount of GR sites which improved ≥1 mm or remained stable during the study period did not differ between MT and PT, but the number of sites worsened ≥1 mm was significantly in favour for PT (MT 23 (25.5%) versus PT 10 (10.6%); p = 0.009). A binary logistic regression identified tooth type (OR = 2.991 for pre-/molar (1.096 [95% CI 1.002-8.933]; p = 0.050)) and manual brushing (OR = 3.341 (1.206 [95% CI 1291-8648]; p = 0.013)) as risk factors for recession impairment at the index teeth. There were no differences between groups for adverse events.

Conclusion: In a population with pre-existing gingival recessions and consequently a high risk of developing further recession the PT seems to be favourable with regard to further development of GR.