Coronectomy of partially erupted lower third molars performed by an undergraduate dentistry student: a case series



The coronectomy technique is an alternative to conventional impacted tooth removal which aims to reduce the risk of damage to the inferior alveolar nerve (IAN). The technique is usually performed by senior oral surgeons or residents in training. Herein, patients were treated in a single service, in which coronectomy was performed by an undergraduate dental student on partially erupted lower third molars.


A prospective analysis was performed on 21 individuals submitted to a total of 35 coronectomies. Clinical and radiographic follow-up was performed for at least 12 months.


Overall, healing was within normal limits, without major complications and without permanent IAN injury. However, one case showed temporary IAN paraesthesia resolved within a month and two required repetitions of coronectomy due to the remaining enamel, but with a good final result. Root migration was observed in all cases, but no other surgery was required.


Coronectomy may be an important option for treating partially erupted teeth in close nerve relationships, which could also be performed by trained undergraduate dental students. This series is interesting because it can encourage oral and maxillofacial surgeons to train undergraduate students and to stimulate their attraction and passion for surgery.

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The authors thank the Coordination for the Improvement of Higher Education Personnel (Finance code 001) for fellowships granted to J.A.A.A. and R.A.M. Mrs. E. Greene provided English editing of the manuscript.


This work was supported in part by grants from the Coordination for the Improvement of Higher Education Personnel (CAPES, Finance Code 001) and PRPq-UFMG (05-2016), Brazil.

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Correspondence to Leandro Napier Souza.

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The study was approved by the Ethics Committee on Human Research of the Institution (No. 59123416.7.0000.5149).

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The patients provided informed consent.

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Mendes, P.A., Neiva, I.M., de Arruda, J.A.A. et al. Coronectomy of partially erupted lower third molars performed by an undergraduate dentistry student: a case series. Oral Maxillofac Surg (2020).

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  • Coronectomy
  • Impacted tooth
  • Oral surgery
  • Third molar