MODEL RELEASED. Toothbrushing. Two year old boy brushes his teeth with an electric toothbrush. The toothbrush, powered by battery, moves across the teeth of its own accord. Children's teeth should be brushed as regularly as possible using a fluoride toothpaste. Correct brushing removes plaque and food particles from dental surfaces and prevents tooth decay. Primary (milk) teeth appear at 6 months and are then gradually replaced by permanent or adult teeth from 6 years of age.