title: Accuracy of the vertical tube shift method in identifying the relationship between the third molars and the mandibular canal.
abstract: OBJECTIVE
  The objective of this study is to assess the accuracy of the vertical tube shift method in identifying the relationship between the mandibular canal (MC) and third molars.
  
  
  METHODS
  Two examiners assessed image sets of 173 lower third molar roots (55 patients) using forced consensus. The image sets comprised two methods: PERI, two periapical radiographs (taken at 0° and -30°), and PAN, a panoramic radiograph (vertical angulation of -8°) and a periapical radiograph taken at a vertical angulation of -30°. Cone beam computed tomography (CBCT) was the reference standard in the study. The responses were recorded for position (buccal, in-line with apex and lingual) and contact (present or absent). The McNemar-Bowker and McNemar tests were used to determine if the PERI and PAN methods would disagree with the reference standard (α = 5 %).
  
  
  RESULTS
  The PERI and PAN methods disagreed with the reference standard for both position and contact (p < 0.05).
  
  
  CONCLUSIONS
  The vertical tube shift method was not accurate in determining the relationship between lower third molars and the MC.
  
  
  CONCLUSIONS
  The vertical tube shift is not a reliable method for predicting the relationship between lower third molars and the MC.
authors.affiliation: Department of Clinical Dentistry, Faculty of Dentistry, Federal University of Espirito Santo, Vitoria, Espirito Santo, Brazil, sergiolinsv@gmail.com.
authors.forename: Sergio Lins
authors.initials: SL
authors.lastname: de-Azevedo-Vaz
authors.forename: Anne Caroline Costa
authors.initials: AC
authors.lastname: Oenning
authors.forename: Marcela Graciano
authors.initials: MG
authors.lastname: Felizardo
authors.forename: Francisco
authors.initials: F
authors.lastname: Haiter-Neto
authors.forename: Deborah Queiroz
authors.initials: DQ
authors.lastname: de Freitas
mesh_terms: D000328:Adult; D054893:Cone-Beam Computed Tomography; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging*; D008340:Mandibular Nerve / Q000000981:diagnostic imaging; D008875:Middle Aged; D008964:Molar, Third / Q000000981:diagnostic imaging* / Q000601:surgery; D010347:Patient Care Planning; D011237:Predictive Value of Tests; D019252:Radiography, Dental, Digital; D011862:Radiography, Panoramic; D012015:Reference Standards; D015203:Reproducibility of Results; D014081:Tooth Extraction; D014092:Tooth Root / Q000000981:diagnostic imaging; D014095:Tooth, Impacted / Q000000981:diagnostic imaging / Q000601:surgery