Children with crooked permanent teeth may be caused by retained milk teeth or supernumerary teeth, which need to be extracted; maxillary incisors will also be crooked when they erupt, and depending on the situation, temporary observation or orthodontic treatment will be chosen. 1. Retained milk teeth: permanent teeth grow crooked due to retained milk teeth, in which case the milk teeth need to be extracted in time so that the permanent teeth can erupt to the normal position. 2. Multiple teeth: permanent teeth grow crooked due to the existence of multiple teeth, in this case, first of all, take a dental apical radiograph, and then promptly remove the multiple teeth, so that the permanent teeth will return to the normal position. 3. Maxillary incisors: the maxillary incisors may be temporarily tilted when they first erupt, and this situation can be temporarily observed; if the permanent teeth are still tilted after tooth replacement, i.e., at the age of 13~14 weeks, it is best to carry out orthodontic treatment in time so as not to affect the dental aesthetics. Children permanent teeth long crooked timely to the hospital, listen to the advice of professional doctors, strictly comply with the medical advice, in order to facilitate the teeth to return to the normal position.