Nylon bristle end-rounding provides important soft tissue benefits to modern toothbrushes. In these studies, the proportion of acceptably end-rounded bristles have been compared for a new rippled bristle design toothbrush (Crest Complete) and a flat bristle control toothbrush (Oral-B). Toothbrush bristles were examined using a stereomicroscope by a grader blind to brush type and assigned empirical grades of acceptable/unacceptable based upon the Silverstone and Featherstone scale used previously in the literature (1988). Thirty brushes of each type (soft and medium texture brushes obtained from commercial sources) were selected and ten random bristles from five randomly selected tufts were isolated for grading. In both soft and medium texture brushes, bristles in Crest Complete demonstrated 89% acceptable end-rounding. These results were significantly different (p less than 0.0001) from those found for the control toothbrush, where 53 and 51% acceptable end-rounding was observed. These results demonstrate the newly designed rippled bristle brush (Crest Complete) exhibits excellent end-rounding.