When the teeth are molars, parents can choose a suitable toothbrush to help their baby brush their teeth with the arc brushing method, which can effectively clean baby’s teeth without damaging the teeth and periodontal tissue. The action is to continuously make circular movements on the tooth surface, so that the toothbrush head keeps turning small circles, bite the incisors first brush the front teeth and then brush the back teeth, brush the upper teeth first and then brush the lower teeth, open the mouth and brush the inside of the teeth, so that each tooth surface is brushed, each part of the tooth surface should be brushed 5-10 circles, each brush about 2 minutes. It should be noted that parents should not use the horizontal brushing method when brushing the baby’s teeth to avoid damaging the child’s tooth enamel, and the body position when brushing is mainly for babies around 1 year old may need two parents to cooperate at the beginning, using a knee-to-knee position, using a relatively gentle force to control the baby’s upper limbs and head. When the baby is lying down, the parents have a wide field of view, it is easy to observe the baby’s reaction to avoid accidental injury, but also a good opportunity for the baby to make eye and body contact, increasing the parent-child relationship. After the baby walks independently, he or she can use the standing position with the back to the parents and facing the position to help brush the teeth, or continue to use the knee-to-knee lying position, advocating rinsing the mouth after meals and brushing the teeth in the morning and evening. Preschoolers have poor dexterity in their hands, so it is advisable to brush teeth twice a day, ensuring that parents help brush teeth once, and then teach children to brush teeth after school.