Hello, at present, most orthodontics is tooth extraction, because the dentition is crowded or the maxillary and mandibular protrusion needs a certain gap to be arranged neatly or retracted, and the cause of these problems is generally because the combined length of one's teeth is greater than the length of one's jaw, which is professionally called that the amount of teeth is greater than the amount of bone. However, tooth extraction can reduce the number of teeth and leave a certain gap, which makes the orthodontic effect better. After the whole orthodontic process, these gaps can be occupied by neatly arranged teeth, and generally no traces of tooth extraction can be seen. If the tooth is not extracted, the whole orthodontics will be very difficult and it will be difficult to achieve satisfactory results!