Coronectomy of impacted mandibular third molars: A meta-analysis and systematic review of the literature

Med Oral Patol Oral Cir Bucal. 2016 Jul 1;21(4):e505-13. doi: 10.4317/medoral.21074.


Background: Coronectomy is an alternative to complete removal of an impacted mandibular third molar. Most authors have recommended coronectomy to prevent damage to the inferior alveolar nerve during surgical extraction of lower third molars. The present study offers a systematic review and metaanalysis of the coronectomy technique.

Material and methods: A systematic review and meta-analysis was performed based on a PubMed and Cochrane databases search for articles published from 2014 and involving coronectomy of mandibular third molars located near the inferior alveolar nerve canal, with a minimum of 10 cases and a minimum follow-up period of 6 months. After application of the inclusion and exclusion criteria, a total of 12 articles were included in the study.

Results and discussion: Coronectomy results in significantly lesser loss of sensitivity of the inferior alveolar nerve and prevents the occurrence of dry socket. No statistically significant differences were observed in the incidence of pain and infection between coronectomy and complete surgical extraction. After coronectomy, the remaining tooth fragment migrates an average of 2 mm within two years.

Conclusions: Coronectomy is indicated when the mandibular third molar is in contact with the inferior alveolar nerve and complete removal of the tooth may cause nerve damage.

Publication types

  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Humans
  • Mandible
  • Mandibular Nerve
  • Molar, Third*
  • Tooth Crown
  • Tooth Extraction*
  • Tooth, Impacted*
  • Trigeminal Nerve Injuries