Children’s new incisors are a little yellow during the tooth replacement period, which may be physiological factors, but also may be caused by poor oral hygiene, enamel hypoplasia and other pathological factors. 1. Physiological factors: tooth enamel is transparent, and then the color of dentin itself is white with yellowish, so the color of dentin through the enamel, sometimes normal. 2. Poor oral hygiene: children who do not pay attention to oral hygiene, do not brush their teeth in the morning and evening, do not rinse their mouths after meals, may lead to residues and dirt sticking to the top of the teeth, teeth look yellow. 3. Poor enamel development: When a child’s enamel is poorly developed or not fully mineralized, it may lead to a yellowish appearance. Children’s new incisors are a little yellow during the tooth replacement period, there may be other reasons, such as tetracycline teeth, etc., it is recommended to consult a doctor in time to find out the cause and treat the symptoms.