Oral and Maxillofacial Surgery

, Volume 23, Issue 4, pp 453–458 | Cite as

Coronectomy: a retrospective outcome study

  • Panagiotis PitrosEmail author
  • Iain Jackson
  • Norma O’Connor
Original Article



Inferior alveolar nerve (IAN) injury is reported as a complication following surgical removal of lower third molars. In cases where the IAN is intimately related to the roots of the tooth, coronectomy may be performed as an alternative. The objectives of this study were to record operative indications for coronectomy and assess the short- and long-term post-operative outcomes following coronectomy.


This retrospective study included patients (19–95 years old) that had coronectomies carried out in the Edinburgh Dental Institute and Chalmers Dental Centre within the last 10 years. The patients were invited by letter to attend a review appointment. High-risk radiographic signs and short- (≤ 3 months) and long-term complications (> 3 months) were recorded.


A total of 124 patients were invited to participate and a total 28 patients returned for review. From the rest of the patients, data was extracted from their dental records. IAN injury was reported in 5 cases (4.3%) as a short-term complication and in 2 cases (3.5%) as a long-term complication. One patient presented with eruption of roots at the review appointment 7 years following surgery. In this study, ‘very’ long-term complications were recorded as the 28 patients that returned for a review, were seen on an average of 4.8 years post-operation.


Coronectomy is a relatively safe technique for preservation of the IAN. However, prospective large scale research is needed to more accurately report on the prevalence of short- and long-term complications.


Coronectomy Surgical extraction Third lower molars Inferior alveolar nerve (IAN) injury 


Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

This study has obtained ethical approval from the NHS Research Ethics Committee of South East Scotland and the NHS Research and Development board.

Informed consent

Informed consent was obtained from all individual participants included in this study.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Oral Surgery, Edinburgh Dental InstituteUniversity of EdinburghEdinburghUK
  2. 2.Chalmers Dental CentreEdinburghUK

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