The steps of root canal treatment mainly include root canal cleaning, root canal sealing and root canal filling. 1. Root canal cleaning: i.e. to clean out the necrotic and inflamed pulp and inflammatory substances in the root canal by medication or mechanical methods; this method can effectively remove the pathogenic substances that cause endodontitis or apical periodontitis. 2. Root canal disinfection: After cleaning the root canal, anti-inflammatory drugs (such as calcium hydroxide, iodoform, etc.) should be sealed in order to adequately disinfect and sterilize the bacteria and residues in the root canal. 3. Root canal filling: After the root canal has been sterilized and the tooth is free from obvious pain and other uncomfortable symptoms, the root canal is filled with special filling materials (such as gum tip) to isolate the invasion of external bacteria and other substances. It is recommended to actively seek medical treatment by a professional doctor.