Clinical outcomes of the crown separation–dislocation–re-segmentation technique for high-risk impacted mandibular third molar extraction: a single-center retrospective cohort study

Background This study evaluated the efficacy and preliminary safety of a CBCT-informed preoperative planning crown separation-dislocation-re-segmentation (SDR) technique for extracting high-risk impacted mandibular third molars adjacent to the mandibular canal. Methods This single-center retrospective observational cohort study reviewed the medical records of patients who underwent extraction of mesially or horizontally impacted mandibular third molars at Tianjin First Central Hospital between January 2024 and December 2025. Patients were categorized according to the surgical technique documented in their medical records, namely the crown separation–dislocation–re-segmentation (SDR) technique or conventional extraction. Treatment allocation was not randomized and had been determined by the operating surgeon during routine clinical care before this retrospective analysis was conducted. Results All procedures were completed as planned. No temporary or permanent IAN injury occurred in the SDR groups, compared with an incidence of 12.50% in the conventional extraction group. VAS scores decreased gradually over time in all groups. On postoperative days 1, 3, and 7, the high-risk SDR group showed lower VAS scores than the conventional extraction group. Minor complications were observed in a few cases, except in the medium-risk group. No significant differences were found in non-neurological complications among the groups. Conclusion The CBCT-informed preoperative planning SDR technique appears to be a safe and feasible approach for the management of high-risk impacted mandibular third molars.