The effects of different levels of brush end rounding on gingival abrasion: a double-blind randomized clinical trial

Abstract

Objective: The objective of this study was to evaluate the effect of different levels of filament end rounding on gingival abrasions (GAs). Methods: The study was a crossover, split-mouth, contra-lateral, double-blinded, randomized design using professional brushing. Three manual toothbrushes, with 0%, 40–50% and >90% end-rounded filaments, were investigated. Participants refrained from all oral hygiene procedures for 48 h prior to each of the three visits. Prior to brushing, oral soft tissue (OST) and GAs were assessed. Based on the randomization, during every visit contra-lateral quadrants were brushed with one of the three test brushes. After brushing, GAs were re-assessed. The means of the GAs prebrushing and post-brushing and differences per brush were calculated. Subanalyses were performed based on the size of the abrasion and its location. Results: A total of 46 generally healthy participants without periodontitis completed the study and provided a full data set. All brushes had statistically significant increases of abrasions following their use (P < 0.001). Non-end-rounded brushes provided significantly more GAs than did the 40–50% and the >90% brushes (P ≥ 0.001). A subanalysis showed that significantly more small-sized (P ≥ 0.002) abrasions located at the gingival margin (P < 0.001) occurred when a non-end-rounded brush was used. No significant differences were found between the 40–50% and >90% end-rounded brushes in any of the analyses. OST deviations were not observed. Conclusions: Based on the results of this experiment involving professional brushing, it can be concluded that 40–50% or greater end-rounded filaments can provide a significant reduction in gingival abrasions compared to non-end-rounded filaments.