When a small tooth erupts next to a large tooth and there is pain, it is important to determine what the cause of the pain is. If it is a small tooth and the nerve is affected by decay due to crowding, it is important to go to the dentistry department in time to take X-rays to determine whether the small tooth can be retained or should be extracted in time. If the small tooth next to the tooth is a multiple tooth, and the multiple tooth is often loose because the root is not strong, causing pain and afraid to bite hard objects, most of the time you need to consider pulling it out. If there is a gap, orthodontic treatment can be considered later. The treatment of a small tooth next to a large tooth is based on whether it is located in a tooth row or is a separate crowded tooth that erupts ectopically to the labial or palatal side, and if it erupts ectopically, it is preferred to consider cleaning it up after an X-ray examination.