Why should I do this? In fact, at present, our root canal therapy is a very effective method to treat our pulp diseases and periapical diseases. Generally speaking, root canal therapy is divided into three steps, so the first step is to clean the pulp, so there may be many methods to clean the pulp. Some doctors may like to take out the pulp directly under anesthesia. Then some doctors will choose to drill a hole in this tooth under anesthesia. After drilling a hole, we will seal the drug that kills the pulp nerve in this hole. Then after a while, the pulp nerve will be necrotic. At this time, the patient basically has no symptoms of his pain. Then we will do the second step after the tooth nerve is completely necrotic. Clean the infected root canal wall and shape it. At the same time, it is necessary to clean the root canal wall by chemical irrigation and this drug sealing method, so that the inflammation can be gradually eliminated. After a period of time, after all the clinical symptoms of this patient disappeared, after our examination, we also found that his bad teeth had no pain symptoms, and the root canal was very clean and there was no exudation. There is no knocking pain and biting pain, so it can be used normally, so we need to use gutta percha, a biocompatible material, to fill this empty root canal system, and finally, complete such a crown closure, so most patients will be advised to have braces repaired after root canal treatment.