Plaque Regrowth Dynamics with Use of an Oscillating-Rotating Electric Toothbrush Measured by Digital Plaque Image Analysis: A Randomized Controlled Trial

This study aimed to compare dental plaque regrowth dynamics across 8 days between an oscillating-rotating (O-R) electric toothbrush and a manual toothbrush using Digital Plaque Imaging Analysis (DPIA). A randomized crossover trial involving adult participants with ≥10% plaque coverage on anterior teeth was conducted. Thirty-four subjects were randomized to one of 4 treatment sequences, each having four 8-day treatment periods. Subjects brushed twice daily with the assigned toothbrush. Morning and afternoon plaque were evaluated on days 1, 3, and 8. The primary variable was afternoon percent plaque coverage, evaluated across 8 days. The O-R toothbrush produced lower mean plaque levels versus the manual toothbrush for all endpoints over 8 days (P≤0.001). The benefit for the O-R toothbrush increased over time, demonstrating 16.4% and 28.1% lower afternoon plaque levels on Days 1 and 8, respectively compared to the manual brush. Trends were similar for morning plaque. Repeated measures analyses showed a 21.2% reduction in overall afternoon plaque and a 23.5% reduction in overall morning plaque for the O-R brush versus the manual brush (P < 0.001). The O-R toothbrush resulted in less overnight and afternoon plaque regrowth versus the manual toothbrush at all time points, and the benefit increased over 8 days.