The same pain after root canal treatment may be caused by the stimulation of the instrument, the inflammation of the apical tissue has not subsided or the infection in the pulp cavity has not been completely removed, etc. According to the different causes of the disease, you can choose the general treatment, medication, and re-endodontics and other ways. 1. Instrument stimulation: after root canal treatment or the same pain, may be the instrument on the root of the tooth around the tissue stimulation effect, generally about a week can be self-healing, you can do a good job of oral hygiene to prevent infection. Avoid eating acidic and cold stimulating food, you can supplement milk, protein and other nutrient-rich substances. 2. Root tissue inflammation has not subsided: after root canal treatment, if it still hurts, it may be the apical tissue inflammation has not subsided, you can go to the hospital to take amoxicillin capsules, ibuprofen extended-release capsules, etc. for anti-inflammatory pain relief. The liver and kidney function should be closely observed during the process of using drugs, and patients who are allergic to drugs should be cautious. 3. Pulp cavity infection is not completely removed: after root canal treatment or the same pain, it may also be the pulp cavity infection is not completely removed, under the operation of the doctor to remove the crown on the closed material, re-root canal treatment. Root canal treatment after toothache is recommended to consult a doctor in time, if you exclude physiological factors, you should improve the relevant examination to clarify the cause of the disease and follow the doctor’s instructions for treatment and medication.