Objective To study the effect of concentrated growth factor (CGF) on gingival healing and bone defect depth in patients undergoing extraction of low-positioned impacted mandibular tooth. Methods A total of 52 patients who underwent extraction of low-positioned impacted mandibular tooth at Zunhua Stomatological Hospital from January 2024 to January 2025 were selected, and they were divided into the control group and the observation group by the random number table method, with 26 patients in each group. The control group received routine suture after tooth extraction, and the observation group received suture after placing CGF in the extraction socket. The gingival healing, bone defect depth, treatment success rate, pain degree, swelling degree and complication rate were compared between the two groups. Results The gingival healing indexes of the observation group on the 3rd and 7th days after operation were lower than those of the control group (P<0.05). The bone defect depth of the observation group on the 7th day after operation was smaller than that of the control group (P<0.05). The treatment success rate of the observation group was 96.15%, which was higher than 80.77% of the control group (P<0.05). The VAS scores of the observation group on the 1st and 3rd days after operation were lower than those of the control group (P<0.05). There was no statistically signiffcant difference in VAS scores between the two groups on the 7th day after operation (P>0.05). The swelling degree of the observation group on the 1st, 3rd and 7th days after operation was smaller than that of the control group (P<0.05). The incidence of complications in the observation group was 7.69%, which was lower than 19.23% in the control group (P<0.05). Conclusion The application of CGF in patients undergoing extraction of low-positioned impacted mandibular tooth has a deffnite effect. It can improve the quality of gingival healing, reduce the depth of postoperative bone defect, effectively alleviate patients' pain and swelling, and help to reduce the incidence of complications, which is worthy of clinical application.