title: Anatomical variations of mandibular canal detected by panoramic radiography and CT: a systematic review and meta-analysis.
abstract: OBJECTIVE
  To investigate the anatomical variations of the mandibular canal through assessment in situ, panoramic radiography, CT or CBCT and assess their frequency.
  
  
  METHODS
  Articles were selected from databases (Cochrane Library, LILACS, ProQuest, PubMed, Scopus, Web of Science and Google Scholar), articles without limitations of language, in which the main objective was to evaluate the frequency of bifurcation of the mandibular canal through assessment in situ, panoramic radiography, CT or CBCT were selected. A meta-analysis of prevalence using random effects was performed.
  
  
  RESULTS
  Using a selection process in two phases, 15 articles were identified, and a meta-analysis was conducted. The results from these meta-analyses showed that the overall prevalence of anatomical variations for in situ studies was 6.46%, and through assessment of panoramic radiography and CT or CBCT the overall prevalence shown was 4.20% and 16.25%, respectively.
  
  
  CONCLUSIONS
  There are two types of variations of the mandibular canal: the retromolar canal and bifid mandibular canal. The frequency variations through assessing in situ, panoramic radiography and CT or CBCT were 6.46%, 4.20% and 16.25%, respectively.
authors.affiliation: 1 Postgraduate Program in Dentistry, Health Sciences Center, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.
authors.forename: Letícia F
authors.initials: LF
authors.lastname: Haas
authors.affiliation: 1 Postgraduate Program in Dentistry, Health Sciences Center, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.
authors.forename: Kamile
authors.initials: K
authors.lastname: Dutra
authors.affiliation: 2 Department of Prosthodontics, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil.
authors.forename: André Luís
authors.initials: AL
authors.lastname: Porporatti
authors.affiliation: 3 Brazilian Centre Evidence-based of Research, Department of Dentistry, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.
authors.forename: Luis A
authors.initials: LA
authors.lastname: Mezzomo
authors.affiliation: 4 Brazilian Centre Evidence-based of Research, Department of Dentistry, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.|5 School of Dentistry, Faculty of Medicine and Dentistry University of Alberta, Canada.
authors.forename: Graziela
authors.initials: G
authors.lastname: De Luca Canto
authors.affiliation: 6 Department of Dentistry, Faculty of Medicine and Dentistry University of Alberta, Canada.
authors.forename: Carlos
authors.initials: C
authors.lastname: Flores-Mir
authors.affiliation: 7 Department of Dentistry, Federal University of Santa Catarina, Florianopolis, Santa Catarina, Brazil.
authors.forename: Márcio
authors.initials: M
authors.lastname: Corrêa
mesh_terms: D063405:Anatomic Variation; D015982:Bias; D054893:Cone-Beam Computed Tomography / Q000379:methods; D006801:Humans; D008334:Mandible / Q000000981:diagnostic imaging*; D011862:Radiography, Panoramic / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: X-ray computed tomography; cone beam computerized tomography; mandibular nerve; panoramic radiography