Re-Intervention Rate, Timing, and Indications Following Coronectomy of the Mandibular Third Molar: A Systematic Review of Systematic Reviews

Background/Objectives: Coronectomy is an alternative to complete third molar extraction to reduce the risk of inferior alveolar nerve injury. This systematic review of systematic reviews evaluates re-intervention rate, timing, and indications after mandibular third molar coronectomy. Methods: A systematic search following PRISMA guidelines was conducted across Scopus, MEDLINE/PubMed, BioMed Central, Web of Science, Cochrane Library and PROSPERO. Studies reporting re-intervention rates after at least six months from coronectomy were included. Data extraction focused on re-intervention timing, indications, and complications. Results: Six systematic reviews, including 5896 subjects and 7913 successful coronectomies (not requiring immediate tooth extractions), were analyzed. The overall re-intervention rate was 4.45%, with timing ranging from six months to ten years (mean: 10.4 months). Root exposure (16.76%) was the primary cause, followed by infection (4.55%) and pain (2.84%). Root migration (12.20%) was common, while inferior alveolar nerve injury remained rare (0.76%). Conclusions: Coronectomy is a viable alternative in high-risk cases, with a low re-intervention rate. Root migration and exposure require long-term follow-up. Standardized imaging protocols and refined re-intervention criteria are needed.