Removal of supragingival plaque in an intraoral model by use of the Sonicare toothbrush.

This study was performed to evaluate plaque removal efficacy of a mechanical toothbrush in a controlled in vivo trial. The study used enamel sections, obtained from extracted human teeth, to evaluate the efficacy of supragingival plaque removal by a mechanical powered toothbrush in various modes of use. Enamel sections were positioned in milled depressions on metal extensions of a maxillary partial denture that bilaterally extended along the buccal corridors. Four sections were used per side, positioned zero, 2 or 3mm from the surface of the metal extension. The prosthesis was worn for 16 hours, whereupon four enamel sections (two per side) were removed. Intra-oral brushing was then performed for 5 or 15 seconds on the remaining four sections. The total of adherent bacteria was then assayed from all enamel sections. Ten to twenty trials were performed (n=4 pairs/trial) for each set of variables. When the electric toothbrush was used as a manual brush ('off'), it was equivalent in plaque removal to a conventional toothbrush (Oral-B 35; P = 0.49). However, when the powered brush was in its active mode ('on'), it removed more bacteria (P < 0.0001); this efficacy was observed even when the bristle tips were at a distance from the plaque surface.