TI11 is an electric toothbrush designed for children aged 0-6. Through the research and exploration of various aspects of children's growth trajectory and brushing needs, specially designed and developed three children's growth stages need to use the brush head. In order to cultivate children's good brushing habits, corresponding solutions are also proposed for the problems of "difficulty in brushing teeth" and "how to brush teeth correctly" encountered by children during their study. At the same time, we also attach great importance to the safety of children's brushing, through the choice of bristles, shape design and material selection are after a lot of attempts to overthrow re-screening. For TI11, it is not only an electric toothbrush used by children to brush their teeth, but also a good partner to accompany children to grow up and guard their teeth.