title: Coronectomy may be a way of managing impacted third molars.
abstract: METHODS
  TPubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL) and the grey literature database SIGLE.
  
  
  METHODS
  Randomised controlled trials (RCTs) and non-randomised controlled trials (CCTs) that compared coronectomy with total removal for third molar extractions with high risk of nerve injury were included.
  
  
  METHODS
  Data were extracted independently and in duplicate by two reviewers. Risk of bias was assessed according to the Cochrane Reviewers' Handbook. Meta-analysis and sensitivity analysis were performed.
  
  
  RESULTS
  Four studies (two RCTs and two CCTs) involving 699 patients and 940 third molars were included. Pooled risk ratios for coronectomy compared with total removal are shown in table 1.Coronectomy was changed to total removal during surgery due to root loosening or mobilisation in 2.3% to 38.3% of cases. In 0% to 4.9% of cases reoperation was required in the coronectomy group due to persistent pain, root exposure or persistent apical infections. Root migration was only reported in three studies and ranged from 13.2% to 85.9%.
  
  
  CONCLUSIONS
  We suggest that coronectomy can protect inferior alveolar nerves in the extraction of third molars with high risk of nerve injury as compared with total removal, and that the risk ratios of post-operative infections were similar between the two surgical modalities.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Hossein
authors.initials: H
authors.lastname: Ghaeminia
mesh_terms: D006801:Humans; D008964:Molar, Third / Q000601:surgery*; D019228:Tooth Crown / Q000601:surgery*; D014081:Tooth Extraction / Q000379:methods*; D061221:Trigeminal Nerve Injuries / Q000517:prevention & control*