The hazards of smoking after tooth extraction include affecting wound healing and easily causing bacterial infection. 1. Impact on wound healing: usually after tooth extraction, there will be wounds at the tooth socket, and smoking smoke nicotine and other harmful substances will stimulate the wound, so that the capillary blockage, and cause blood clotting off, the coagulation function will be affected, and is not conducive to the healing of the wound of tooth extraction. And smoking “sucking” action is also easy to aggravate the wound bleeding. Therefore, you should not smoke after tooth extraction. 2. Easy to cause bacterial infection: If you smoke after tooth extraction, the wound site is prone to residual large amounts of nicotine and other harmful substances, which will greatly increase the probability of bacterial infection, and will easily lead to inflammatory reactions, such as periodontitis, gingivitis, etc., with pain, generalized fever and other symptoms. Smoking after tooth extraction has more harm, it is recommended not to smoke after tooth extraction, usually pay attention to keep the mouth clean to promote wound healing.