Root fracture with retention of an apical fragment is among the most frequently encountered intraoperative complications of exodontia, reported in an estimated 15 37% of extractions in historical series and in up to 86% of sites when post-extraction imaging is used systematically to detect fragments that clinical inspection alone misses.1 This narrative review examines the clinical, radiographic and ethico-legal literature on retained root fragments to determine under what circumstances planned retention is defensible, and what obligations attach to the clinician when a fragment is left — whether by deliberate decision or unplanned fracture. Retrospective and histological series indicate that small, deeply positioned, non-mobile, non-infected fragments in teeth without periapical pathology are frequently well tolerated, healing beneath an intact layer of cementum and bone.2,3,4 This underlies the accepted practice of coronectomy for third molars in close proximity to the inferior alveolar nerve, and of intentional partial root retention adjacent to implants and in intentional replantation protocols.5,6,7,8 However, fragments that communicate with the oral cavity, are infected, mobile, or associated with periapical disease carry a materially higher risk of persistent infection, cyst formation, pain and, in implant sites, retrograde peri-implantitis and implant failure.1,2,7 Medico-legal case series show that adverse outcomes and successful negligence claims involving retained roots arise less from the retention itself and far more from failure to detect the fragment, failure to document it, and failure to disclose it and its implications to the patient.9,10,11,12,13 The review concludes that no fragment size or retention decision is categorically ―without issue,‖ and that ethical and legal defensibility rests entirely on individualised risk assessment, post-extraction radiographic confirmation, informed consent that is contemporaneously documented, and structured follow-up — not on a blanket assumption that retention is inconsequential.

References

1. Rasner SL. Common extraction complications and solutions. Dent Today. 2022 Sep 13. Available from: https://www.dentistrytoday.com/common-extraction-complications-and-solutions/

2. Nayyar J, Clarke M, O’Sullivan M, et al. Fractured root tips during dental extractions and retained root fragments. A clinical dilemma? Br Dent J. 2015;218(5):285–90.

3. Helsham RW. Some observations on the subject of roots of teeth retained in the jaws as a result of incomplete exodontia. Aust Dent J. 1960;5(2):70–7.

4. Glickman I, Pruzansky S, Ostrach M. The healing of extraction wounds in the presence of retained root remnants and bone fragments: an experimental study. Am J Orthod Oral Surg. 1947;33:263–83.

5. Patel V, Moore S, Sproat C. Coronectomy — oral surgery’s answer to modern day conservative dentistry. Br Dent J. 2010;209(3):111–4.

6. Renton T, Hankins M, Sproate C, McGurk M. A randomised controlled clinical trial to compare the incidence of injury to the inferior alveolar nerve as a result of coronectomy and removal of mandibular third molars. Br J Oral Maxillofac Surg. 2005;43(1):7–12.

7. Uyguc E, Yaylaci E, Koyuncu B, Kumbuloglu O. Implant osseointegration adjacent to a retained root fragment: a case with 11-year follow-up. Case Rep Dent. 2025;2025:5547549.

8. Lin Z, Huang D, Huang S, et al. Expert consensus on intentional tooth replantation. Int J Oral Sci. 2025;17(1):16.

9. Medical and Dental Defence Union of Scotland. Broken root [case file]. 2019 May 29. Available from: https://www.mddus.com/resources/resource-library/case-files/2019/may/broken-root

10. Medical and Dental Defence Union of Scotland. Root fragment [case file]. 2020 Jun. Available from: https://www.mddus.com/resources/resource-library/case-files/2020/june/root-fragment

11. Dental Protection. The retained root and consent. 2021 Aug 10. Available from: https://www.dentalprotection.org/hongkong/publications-resources/articles/articles/the-retained-root and-consent-int

12. Dental Protection Australia. Tricky extraction leads to hospital admission [case study]. Available from: https://www.dentalprotection.org/australia/publications-resources/case-studies/case-studies display--/tricky-extraction-leads-to-hospital-admission-aus

13. DWF Group. Informed consent to dental treatment: impact on negligence claims. 2023 Jul. Available from: https://dwfgroup.com/en/news-and-insights/insights/2023/7/informed-consent-to dental-treatment-impact-on-negligence-claims

14. Burger R, Smit M, Plenge U, Gibbs MW. Informed consent for peripheral nerve blocks at a tertiary level hospital in South Africa: a quality improvement project. South Afr J Anaesth Analg. 2024;30(2):62–6.

15. Mamoojee A, Alli A. Anaesthetists’ knowledge of South African Law pertaining to informed consent in an academic centre. South Afr J Anaesth Analg. 2018;24(6):14–23.