Animal and clinical studies have shown that sharp, unpolished toothbrush bristles may injure gingival tissue, and their contribution to cervical abrasion is widely discussed. The aim of the present study was to compare the end-roundness and smoothness of the bristle tips of ten commercially available children's toothbrushes (Elmex Lernzahnbürste, Aronal Oko Dent Kinder, Signal Kids, Dr. Best Milchzahn, Dr. Best Best Friends, Colgate Grip'Ems, Colgate My First, Oral B Mickey for Kids, Oral B Disneys' Mickey Mouse, Blend-a-med Blendi). From forty brushes five tufts each were selected randomly and subjected to scanning electron microscopy (45 degrees) at a viewing angle of 45 degrees. On micrographs six bristles located in the first three rows that could clearly be evaluated were analyzed visually for end rounding and evaluated by shape factor (SF) analysis by a blinded single examiner. Mean SF was reported highest for Aronal Oko Dent Kinder at 0.278 (+/- 0.004) followed by Dr. Best Milchzahn (0.277 [+/- 0.005]) and Elmex Lernzahnbürste (0.277 [+/- 0.005]). These values were significantly different from those found for Colgate My First (0.258 [+/- 0.023]) and Colgate Grip'Ems (0.267 [+/- 0.012]) (p<0.001; ANOVA, Bonferroni). More than half of the surfaces of the bristle tips examined were rated as non-acceptable for Signal Kids (75%) and Dr. Best Best Friends (100%). For all the other brands more than 50% of the bristle surfaces were judged as being acceptable. Despite of being flattened during usage, rounded bristle tips with a smooth surface are desirable. A good quality of bristle tips could only be observed in half of the brands examined.