In clinical work, there are also many times when general anesthesia is not required but only local anesthesia is needed to complete the surgery, local anesthesia has the following methods in common: 1. The local anesthetic is injected into the nerve trunk or its main branches to block the afferent stimulation of the nerve endings, so as to produce anesthesia in the area of the nerve distribution that is blocked; 4, regional block anesthesia; 5, anesthesia for tooth extraction surgery, which is mostly done by the dentist.