As to whether a child’s decayed milk tooth needs root canal treatment, it is necessary to check the depth of decay and symptoms of the decayed milk tooth. If the decayed tooth is relatively shallow and does not reach the adjacent pulp, root canal treatment is not necessary, and the decayed decayed material should be removed by special high-speed turbine drill and filled with filling material. However, if the decayed area is deeper and has invaded the pulp of the milk tooth, and the child has obvious painful feeling, most of them have developed to the stage of milk tooth pulpitis, then root canal treatment is needed. In addition to pulp opening and drainage, the pulp of the baby tooth needs to be extracted and root canal treatment of the baby tooth is performed. If available, a preformed crown of the baby tooth may also be considered to protect the baby tooth.