Abstract: Objective: To observe the clinical effects of multi-slice helical CT(MSCT) three-dimensional reconstruction in the minimally invasive extraction of impacted maxillary teeth.Methods: The data of 50 patients with impacted maxillary teeth treated with minimally invasive extraction using the MSCT three dimensional reconstruction guiding(the observation group) were retrospectively analyzed,50 patients with impacted maxillary teeth treated with hammer method were set as the control group.The duration of extraction and the occurrence of intraoperative and postoperative complications between two groups were compared.Results: The operations of two groups were successful.The extraction duration of the observation group and control group were(19.5±5.5) min and(35.5±8.5) min,respectively,the difference of which was statistically significant(P<0.01).The degree of pain and swelling,and incidence of the adjacent teeth damage in observation group were less than those in control group(P<0.05 to P<0.01).Conclusions: The MSCT three dimensional reconstruction can clearly observe the three-dimensional position of impacted teeth in the jaw from different angles and levels,and intuitively and accurately judge the relationship of impacted teeth and surrounding tissue.It can provide the basis for operative accurate approach,reduce the duration,injury and intraoperative and postoperative complications,which is worth further popularizing in clinical use.