Swelling and pain after wisdom tooth extraction is a common clinical symptom. For swelling after tooth extraction, there is usually no obvious swelling after simple tooth extraction, such as extraction of anterior teeth and extraction of milk teeth, and patients may have mild pain or even no pain and swelling after extraction. However, for the extraction of wisdom teeth, especially the extraction of obstructed wisdom teeth, because the extraction process often involves the incision and flap of the gums, patients often have obvious swelling and pain after the extraction, which is a normal physiological phenomenon within 2-3 days after the extraction, and there is no need to worry about it at all. However, if the swelling persists and the pain gradually worsens more than 3 days after wisdom tooth extraction, it must be alerted that it is not a mere postoperative physiological swelling, but an infection of the postoperative extraction wound.