Pain after root canal sealing is a stress reaction caused by drugs (such as inactivators or anti-inflammatory drugs) acting on the pulp of the tooth, and must be treated by a doctor for root canal opening pain relief. 1. Inactivators (i.e. nerve killing drugs): they can act on the inflamed nerve to make it gradually lose its biological activity, and the process usually takes one to two weeks; therefore, there will be slight pain and discomfort when the drug is first sealed, but the symptoms will be gradually reduced, and if the pain is not relieved or even aggravated, then it is necessary to seek medical treatment to open the root canals and place the pain medication in order to quickly stop the pain. 2. Root canal anti-inflammatory drugs: After root canal preparation, special root canal anti-inflammatory drugs should be placed inside the root canal to remove the inflammatory substances inside the root canal; they are slightly irritating, and will cause slight pain and discomfort after sealing the drugs, if the pain symptoms worsen, it is recommended to seek medical attention to open the root canal with rinsing in order to effectively relieve pain. If the above symptoms are aggravated, it is recommended to consult a doctor for symptomatic treatment. If the symptoms cannot be treated in time, anti-inflammatory drugs (e.g., amoxicillin, metronidazole) or painkillers (e.g., ibuprofen) may be taken as prescribed by a doctor to alleviate the symptoms.