AIM:To investigate the effect of locally used Shahaosan on preventing the complication of extraction of impacted tooth.METHODS: 274 cases patients with extraction of impacted teeth were randomly devided into 3 groups named A,B and C.Shahaosan and Yunnan white drug were processed into drug A and B by department of pharmacy with the same color, shape and quality which are blind to doctors and patients.When the impacted teeth were extracted, administed group A(92 cases) with drug A,group B(86 cases) with drug B and group C(96 cases ) was a blank control. After the operation,incidence and severe intensity of dry socket in each group were observed and evaluated by scores.RESULTS: The incidence of dry socket in group A,B and C were 0.09% (1/92),2.32% (2/86),8.33% (8/96).There was no significant difference between group A and B, group B and C, while a significant difference showed between group A and C.The PoSSe score in group A, B and C was 19.36, 27.80 and 22.83 respectively.Afer the experiment the department of pharmacy informed that drug A is Shahaosan and drug B is Yunnan white drug.CONCLUSTON:Compiments of dry socket induced by extracting of lower jaw impacted teeth can be prevented by locally administered with Shahaosan, but no significant effect of alleviating the symptom of dental extraction.