The tooth extraction operation (especially the extraction of obstructed wisdom teeth) itself is a surgical operation, and since it is a surgery, different degrees of pain, swelling, bleeding and even other complications such as infection, nerve damage and root fracture will definitely occur during or after the operation, so it is very important to prepare well before the operation and to be familiar with the precautions to be taken after the extraction and strictly comply with them to reduce the postoperative complications. 1., Psychological preparation. Psychological preparation is the most important, because if you cannot accept the postoperative pain, bleeding, swelling, which will definitely happen, or complications with a certain chance of occurrence such as root fracture, infection, nerve damage, or fear of the extraction environment, distrust of the doctor, etc., it is recommended to withhold tooth extraction. Good psychological preparation can reduce the postoperative discomfort, and negative emotions such as psychological fear may magnify the postoperative pain and other discomfort. 2. Control the inflammation of teeth, that is to say, teeth cannot be extracted when there is toothache and teeth can only be extracted when there is no pain. 3. Women should avoid menstruation and pregnancy. Teeth should not be extracted during menstruation, and teeth should not be extracted during the first and second trimesters of pregnancy. Before extracting teeth for breastfeeding women, please consult your pediatrician if you can take oral antibiotics, and you may need to replace breastfeeding with formula if necessary. 4. You should not fast before surgery and eat to avoid fainting caused by low blood pressure, low blood sugar, etc. 5. Avoid staying up late, fatigue, drunkenness and cold before surgery. If you need to travel within three days after tooth extraction (such as doing airplane or long-distance train) or must attend important meetings, lectures or participate in strenuous sports, etc., it is recommended that tooth extraction be done at a later date. 6. If you have serious systemic diseases, such as hypertension, heart disease, diabetes, abnormal liver and kidney functions, blood diseases, etc., you should inform the doctor in advance and suspend the extraction or make an appointment for extraction under cardiac monitoring. 7. If there is a history of drug allergy or other special conditions, the doctor should also be informed in advance. 8. If there are other cases that are not outlined, you are welcome to ask questions in the consultation area and I will reply to you as soon as possible.