The pain after tooth extraction is usually seen in the case of more invasive tooth extractions, such as the extraction of buried wisdom teeth, which involves a series of operations such as gingival incision and flap, and bone removal and tooth division, which are relatively more invasive and take longer time. After this type of tooth extraction, the patient has a normal physiological pain process. If the pain is tolerated by the patient, there is no need to apply pain medication, but if the pain is severe, some pain medication can be applied as appropriate, commonly known as the first step of pain relief and analgesic drugs. For example, Fenbid, acetaminophen and so on, this kind of drugs can be used by patients. However, if the wound is more painful than 3 days after tooth extraction, accompanied by redness, swelling and overflowing pus of the extraction wound, it is possible that the pain is caused by infection after tooth extraction, so it is necessary to visit the stomatology department again to clean and scrape the extraction wound and apply anti-inflammatory drugs for the whole body to control the infection and avoid further spread of the infection, so as to control the pain caused by this kind of infection.