Root canal treatment pain after the second time is related to the individual’s physical condition, generally a slight pain is normal, if the pain is obvious or aggravated for the abnormal phenomenon need to go to the hospital for treatment. 1. Slight pain. Root canal treatment after the second time may be the root filling has been completed or in the stage of drug replacement, some patients due to different physical condition will appear slight pain, may be due to the treatment process of drug rinsing or drugs into the root canal caused by reactive pain, general mild pain is normal, can be temporarily observed. 2. Pain is obvious or aggravated. If the pain is obvious or aggravated after the second root canal treatment, it may be caused by the body’s sensitivity to the drugs or due to the inflammation that has not been eliminated, so it is necessary to go to the hospital immediately to replace the drugs or open the pulp drainage treatment. If the pain is obvious after the second root canal treatment, it is recommended to go to the hospital in time.