Before wisdom tooth extraction, an examination is definitely necessary. Firstly, the patient needs to be interviewed to check whether the patient has any underlying diseases affecting the whole body such as high blood pressure, diabetes, heart disease. Secondly, it is necessary to check how many wisdom teeth have erupted in the mouth. The second step is to check how many wisdom teeth have erupted in the mouth and how many are blocked, and the other thing that must be done is an imaging examination of the wisdom teeth, usually a dental film or a full-mouth body surface photography, to see the number of roots, the distance to the inferior alveolar nerve vessels and whether the wisdom teeth have mutations and other special conditions. In addition, if conditions permit, it is recommended that the patient’s blood be examined for abnormalities in blood count and coagulation function.