The reasons why babies do not grow teeth include the following: 1, genetic factors: when parents erupt teeth too late, children may show late teething. 2, lack of nutrition: baby gastrointestinal function is weak, poor food digestion, long-term lack of nutrition will cause the body’s development is delayed, dental embryo calcification time is delayed, so there is a long time no teeth phenomenon. 3, fibrous tissue hyperplasia: baby often chew the texture of tough Food, resulting in gum thickening, the formation of fibrous tissue hyperplasia. If the baby’s gums thicken due to frequent gnawing on tough food, the gum thickens and fibrous tissue proliferates, making it difficult for the embryo to erupt, and if necessary, the soft tissues should be removed and a guide should be performed.