2026 Volume 21 Issue 1 Pages 2-15
The aim of this study was to examine the effects of toothbrush bristle shape, including round, tapered, and spiral, as well as brushing pressure and stroke width on plaque removal rate. Using a jaw model, artificial plaque was applied to resin teeth, then brushing was performed on the buccal side using a scrubbing technique-based method. Three different brushing pressures (100, 150, 200 g) and stroke widths (10, 15, 20 mm) were tested for each toothbrush type, and quantitative measurements of the areas of removed plaque were performed using the ImageJ software package. For each combination of brushing pressure and stroke width, plaque removal rates were measured in triplicate, with the mean values obtained used for comparative analysis among the different conditions.
A comparison of plaque removal rates associated with bristle shape showed that round and spiral bristles achieved significantly greater plaque removal than tapered bristles. Regarding the correlation between brushing variables and performance, the plaque removal rates of round bristles were found to be positively correlated with brushing force and those of tapered bristles with stroke width, while those of spiral bristles showed a positive correlation with both brushing force and stroke width. Spiral bristles and round bristles tended to have higher plaque removal rates than tapered bristles, and, under certain conditions, spiral bristles demonstrated the highest removal rate.
The highest plaque removal rate was observed with spiral bristles used at a high brushing force (200 g) and large stroke width (20 mm).
