A prospective clinical study to evaluate the effect of manual and power toothbrushes on pre-existing gingival recessions

To evaluate gingival recession changes after six months of brushing with an oscillating-rotating power toothbrush (PT) or an ADA reference manual toothbrush (MT).

Healthy subjects with pre-existing recession were assigned to brush with either a PT (n=55) or an ADA reference MT (n=54) according to a prospective randomized, controlled, single-blind, parallel group design. Participants were asked to brush their teeth twice daily for two minutes each with the same fluoride toothpaste. Clinical attachment loss and probing pocket depths (PPDs) were measured at six sites per tooth to the nearest mm by one calibrated examiner at baseline and after six months. Gingival recession was calculated as the differences between clinical attachment loss and PPDs overall and separately at individual sites.

As compared with baseline, overall recession at six months was reduced from 2.35 +/- 0.35 mm to 1.98 +/- 0.55 mm (p<0.001) in the PT group and from 2.26 +/- 0.31 mm to 1.90 +/- 0.45 mm (p<0.001) in the MT group. The data showed 40% (power) and 38% (manual) of all recession sites improved by at least 0.5 mm while 51% and 54% remained unchanged. Eight percent and 7% recessions increased over time. Differences between groups were not statistically significant at either timepoint.

Both the PT and the MT significantly reduced pre-existing gingival recession after six months of brushing. This may have been due to improved brushing technique (i.e., Hawthorne effect).

Based on these six-month data, concern that power tooth brushing results in a higher risk for gingival recession is not warranted.