Whether or not to extract a necrotic tooth should be decided by the doctor after examination based on factors such as whether or not the tooth has any retention value and the length of the root. 1. Whether there is any retention value: if it is wisdom teeth, misaligned teeth, multiple teeth and other teeth with no retention value, you can generally consider extraction, but it is best not to extract the tooth during the acute inflammation. If it is a normal tooth necrosis, should go to the regular hospital for root canal treatment, as far as possible for retention, try not to pull. 2. Root length: If the X-ray shows that the length of the root is close to the normal physiological range, and there is no obvious loosening, the root canal treatment can be carried out after porcelain or all-ceramic crown restoration. If the X-ray shows that the root of the tooth is shorter, the root of the longitudinal fracture, generally need to be extracted, otherwise it may cause recurrent inflammation of the oral teeth, can be extracted in the regular hospital to do implant denture repair. Necrosis of the tooth to be extracted, to the hospital in a timely manner, under the guidance of the doctor standardized treatment.