Sonic toothbrushes are developed for children of different ages. They differ mainly in the speed of movements and the fineness of the bristles. For children aged:
3 - 6 years, use the TrueLife SonicBrush Baby G with extra-fine bristles and 32,000 movements per minute
5 - 9 years use the TrueLife SonicBrush Kid G with the softest bristles and 48,000 strokes per minute
7 - 14 years use the TrueLife SonicBrush Junior J100 with finer bristles and 56,000 strokes per minute