Once your child has a few teeth, you can start using toothpaste on the brush. Use only a tiny amount for each cleaning, and be sure to choose toothpaste without fluoride for children under two, as too much fluoride can be dangerous for very young children. Always have your child rinse and spit out toothpaste after brushing, to begin a lifelong habit he’ll need when he graduates to fluoride toothpaste. Children naturally want to swallow toothpaste after brushing, and swallowing too much fluoride toothpaste can cause teeth to stain. You should brush your child’s teeth for him until he is ready to take on that responsibility himself, which usually happens by age six or seven.