There is no 1 100% sure answer to the question of how long after wisdom tooth extraction does not bleed, from half an hour after the operation to 24h after the operation, which may be the normal situation. Generally, after the wisdom tooth is extracted, the doctor will ask the patient to bite on the sterile cotton ball or cotton roll for 30 minutes, which is mainly to play the role of pressure to stop bleeding, because the extraction wound just formed, there will certainly be a process of blood seepage. The time of blood clot formation in the extraction wound is around 15-30min, so it is normal for the wound to ooze blood within this time period. Sometimes, due to the large trauma of tooth extraction, there will be a process of blood in the sputum in addition to blood oozing from the wound. This process may be within 24h after surgery, which means that 24h after surgery, blood in sputum is also considered normal. If these conditions are not present, but there is an obvious bleeding from the extraction wound, then it is possible that the bleeding is pathological postoperatively, and the patient is advised to visit the dentistry department again for a review and treatment for this obvious bleeding.