Root canal treatment is currently the most popular endodontic treatment method with the best treatment effect and the least complications in clinical practice. The steps of root canal treatment are divided into the following steps: 1. pulp opening, fully exposing the pulp cavity, completely removing the pulp and removing the infected material in the root canal. 2. root canal preparation, using special instruments for dentistry, to prepare the root canal where the root canal is not open and narrow, so that the root canal is open to facilitate the drainage of inflammatory material, and root canal rinsing and disinfection. 3. seal the root canal, anti-inflammatory and disinfection treatment. 4. After the inflammation has completely subsided, the root canal is permanently filled with special materials for dentistry to isolate external stimulation and prevent reinfection.