['The aim of the study was to compare the efficacy of four most commonly used bristle designs of toothbrushes in plaque removal.', 'The study was a randomized 4 cell, examiner blind cross-over design assessing the plaque removal efficacy of all four brushes on a single occasion. Sixteen subjects aged 14-15 years participated in the study. On day 1 of each test period, the subjects were rendered plaque free and were asked to suspend oral hygiene practices for 24 hours. On day 2, the subjects were scored for plaque prior to brushing using the Turesky-Gilmore modification of Quigley-Hein plaque index. The subjects then brushed with the allocated toothbrush for 2 minutes and the post-brushing plaque scores were assessed. A wash-out period of 4 days was allowed between the test periods.', 'All the brushes showed a significant reduction in the post-brushing plaque scores ( p < 0.001). The mean reduction in the plaque scores for all the brushes was around 53%. The percentage plaque reduction was greater in the anterior surface than the posterior surface (59.6 +/- 7.45% vs. 49.83 +/- 4.35%). The percentage plaque reductions in the upper, lower, buccal and lingual surfaces were similar. No significant difference in the reduction of plaque scores between the four brushes was seen.'] Do a comparative study of the efficacy of four different bristle designs of tooth brushes in plaque removal?