this has little impact. The occlusal relationship between the upper and lower teeth is the most important to maintain the normal function of the oral and maxillofacial system. The teeth are arranged neatly and the occlusal relationship is good, which is very important for the health of the entire oral and maxillofacial system and the maintenance of oral cleanliness. Compared with the whole oral and maxillofacial system, the retention of individual teeth is not the main thing, and orthodontic tooth extraction generally pulls out bicuspids or decayed teeth that are not important in function. As long as the remaining teeth are healthy, there is no problem.