Baby C, born naturally in the maternity ward, was delivered at full term and the family couldn’t be happier. The family was surprised to learn that the baby had a tooth and it wiggled when touched. The milk teeth that are present at birth are called birth teeth, also known as birth teeth, mostly found in the lower incisors, and their incidence is about 1 per 1,000. Birth teeth are the premature eruption of milk teeth, because of too early eruption, most birth teeth are underdeveloped, no roots or very short roots, teeth are very loose, easy to fall off caused by accidental inhalation of the trachea caused by asphyxia; may also affect the child sucking, cause sublingual traumatic oral ulcers, bite mother’s nipples and so on. Loose rootless birth teeth should be extracted, and the extraction usually does not affect the eruption of permanent teeth. If they are not loose and are normal, they should be retained so as not to cause the loss of milk teeth. The retained birth teeth mostly grow in the lower jaw. When the mother is breastfeeding, she should hold up the breast in the shape of C with one hand, stimulate the baby’s upper and lower lips with the nipple, and quickly put in the nipple and areola once the baby’s mouth is open; at the end of breastfeeding, a finger should be inserted from the corner of the baby’s mouth and then withdraw the nipple, which can help avoid nipple injury or the birth teeth falling out on their own.