A well-performed root canal in a baby tooth will not affect the permanent tooth; a poorly performed root canal may cause infection of the permanent tooth germ. Root canal treatment of milk teeth with perfect root filling usually has no effect on permanent teeth and will lead to normal eruption of permanent teeth. If the root canal treatment of milk teeth is poor, the inflammation of the apical part of the root is not completely controlled, and the mucous membrane redness and swelling or gingival pustules appear repeatedly in the mouth, it will affect the permanent tooth embryo for a long time, resulting in the difficulty of eruption of the permanent tooth or ectopic eruption, and the seriousness of it will also cause permanent tooth lesions. Therefore, the quality of root canal treatment for milk teeth has an impact on permanent teeth, and once caries or pulpitis occurs in milk teeth, it needs to be treated as soon as possible, and should go to the regular medical institutions for medical treatment.