Objective To explore the application of extraoral digital radiography (DR) for the third molar in impacted tooth extraction. Methods A total of 58 patients undergoing impacted tooth extraction in the Stomatological Hospital of Zhejiang University School of Medicine from May 2024 to May 2025 were selected. According to the random number table method, they were divided into the control group (n=29) and the observation group (n=29). The control group was examined with traditional dental radiography, and the observation group was examined with extraoral DR for the third molar. The inclined vertical angle, root apex exposure time, pre-extraction tooth length and aesthetic correction effect were compared between the two groups. Results The inclined vertical angle in the observation group was higher than that in the control group, and the root apex exposure time was shorter than that in the control group (P<0.05). There was no statistically significant difference in the pre-extraction tooth length measurements between the observation group and the vernier caliper (P>0.05). There was a statistically significant difference in the pre-extraction tooth length measurements between the control group and the vernier caliper (P<0.05). The effective rate of aesthetic correction in the observation group (100.00%) was higher than that in the control group (79.30%) (P<0.05). Conclusion Compared with traditional dental radiography, extraoral DR for the third molar in patients undergoing impacted tooth extraction can increase the inclined vertical angle, shorten the exposure time, and reduce the measurement error of the pre-extraction tooth length. It can obtain higher image quality, and effectively improve the effect of aesthetic correction.