Impact of brushing-flossing sequence on plaque removal: a single-blind, randomized controlled trial

Brushing and flossing have been widely used worldwide as mechanical ways for the removal of dental plaque. The aim of this study was to investigate whether the sequence of brushing and flossing would have an impact on the efficacy of plaque removal. A total of 56 college students were randomly assigned to the floss-brush group and the brush-floss group. A baseline plaque index (PI) assessment was performed on the participants, followed by oral hygiene instruction on the modified Bass brushing technique and flossing methods. The participants in the floss-brush group were directed to floss before brushing their teeth, while the brush-floss group executed the same tasks, differing only in the order of operations. The Turesky Modified Quigley-Hein Plaque Index (TMQHPI) was utilized to assess total, buccal, lingual, and interproximal plaque, with results deemed statistically significant at p < 0.05. Values are presented as mean ± standard deviation (mean ± SD). The floss-brush group exhibited significantly greater mean ± SD reductions in PI compared to the brush-floss group in the maxillary anterior region for both total surfaces (1.13 ± 0.87 vs. 0.71 ± 0.89; p = 0.011) and interproximal surfaces (1.15 ± 0.92 vs. 0.65 ± 0.86; p = 0.01), as well as in the mandibular anterior region for total surfaces (0.91 ± 0.76 vs. 0.64 ± 0.95; p = 0.026) and interproximal surfaces (0.93 ± 0.80 vs. 0.62 ± 0.96; p = 0.031). No statistically significant difference was identified between the two groups in other regions. Our results suggest a potential advantage of flossing followed by brushing in anterior regions, evidenced by greater PI reduction compared to brushing then flossing. (23-07-2024) on https://www.chictr.org.cn/ with the ID (ChiCTR2400087214).