Most of the anesthetics used for tooth extraction maintain anesthesia for 2-3 hours and then lose its effect. Tooth extraction is a common treatment technique in dentistry and requires pre-anesthesia before extraction to reduce pain. Currently, the two main types of anesthesia used for tooth extraction include local infiltration anesthesia and nerve block anesthesia. Local infiltration anesthesia is more widely used, with ativan hydrochloride injection being the most widely used, and this anesthetic can be maintained for 2-3 hours. Nerve block anesthesia is mainly used in the extraction of mandibular posterior teeth, which is often used in conjunction with local infiltration anesthesia, and block anesthesia is more commonly used with lidocaine injection, which can generally last for 2-3 hours. However, it should be noted that the loss of anesthetic effect does not mean that the anesthetic is metabolized cleanly, and generally the anesthetic used for tooth extraction can be metabolized basically only 48 hours after surgery. It is recommended to choose a regular hospital for tooth extraction, so as to avoid the appearance of complications such as local hematoma, bleeding and nerve numbness that may be caused by improper anesthesia methods.