Root canal treatment generally does not appear obvious pain, the current clinical root canal treatment is basically a painless operation, if the pain can be injected with local anesthesia, so there is no need to worry too much. Root canal treatment refers to the systematic treatment process of pulp deactivation, root canal preparation and root canal filling for teeth with pulpitis, apical periodontitis and other diseases. The first step of root canal treatment is to open the pulp and then deactivate it. If the pulp is not necrotic, the tooth may experience pain, and in order to prevent severe pain, the doctor will usually administer local anesthesia to the tooth before starting the treatment so as to ensure a painless operation; if the pulp is already necrotic, the process will not cause any pain. The second step of root canal treatment is root canal preparation, which refers to the use of instruments such as root canal files to clean out the infected material in the root canal. If there is any remaining pulp in the root canal during this process, the tooth may also experience slight pain, and if the pain is obvious, it is necessary to use inactivation agents again to completely kill the pulp, and then carry out the root canal preparation again to make sure that all of the pulp has been killed. The final step of root canal treatment is root canal filling, which generally involves the use of a root canal filling agent as well as a cement tip to fill the root canal tightly. If the filling material exceeds the apical foramen, the tooth may experience slight pain, so a professional dentist is required to determine the root length before the filling is performed. Each step of the root canal treatment is basically a painless operation and it is advisable to visit a professional dentist for the treatment.