title: Comparison of cone-beam volumetric imaging and combined plain radiographs for localization of the mandibular canal before removal of impacted lower third molars.
abstract: OBJECTIVE
  The removal of third molars requires information about the relative position of the root tips and the mandibular nerve. The diagnostic value of conventional radiologic procedures using a panoramic radiograph and symmetrical PA cephalometric radiograph (PAN&PA) was compared with that of a cone-beam volumetric imaging (CBVI) device (Galileos; Sirona, Bensheim, Germany).
  
  
  METHODS
  Six observers evaluated 30 PAN&PA and 30 CBVI for the position of root tips. Diagnostic information was rated from 1 to 5 (excellent to poor).
  
  
  RESULTS
  With PAN&PA, 3 times more scans showed nondetectable information for horizontal position compared with CBVI. The diagnostic information in the vertical dimension received a median rating of 2 (good) for CBVI and for PAN & PA; for the horizontal dimension, CBVI received a median rating of 2 (good), compared with a significantly worse median rating of 3 (sufficient) for PAN & PA (P = .000). The variance was highest for the horizontal dimension with PAN & PA (1.27).
  
  
  CONCLUSIONS
  These findings indicate that cone-beam technology improves the localization of third molar for presurgical planning.
authors.affiliation: Department for Craniomaxillofacial and Plastic Surgery, University of Cologne, Cologne, Germany. joerg.neugebauer@uk-koeln.de
authors.forename: Joerg
authors.initials: J
authors.lastname: Neugebauer
authors.forename: Rusbeh
authors.initials: R
authors.lastname: Shirani
authors.forename: Robert A
authors.initials: RA
authors.lastname: Mischkowski
authors.forename: Lutz
authors.initials: L
authors.lastname: Ritter
authors.forename: Martin
authors.initials: M
authors.lastname: Scheer
authors.forename: Erwin
authors.initials: E
authors.lastname: Keeve
authors.forename: Joachim E
authors.initials: JE
authors.lastname: Zöller
mesh_terms: D002508:Cephalometry; D054893:Cone-Beam Computed Tomography; D006801:Humans; D008334:Mandible / Q000000981:diagnostic imaging*; D008340:Mandibular Nerve / Q000000981:diagnostic imaging*; D008964:Molar, Third / Q000000981:diagnostic imaging; D011300:Preoperative Care; D011861:Radiography, Dental / Q000379:methods*; D011862:Radiography, Panoramic; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D014081:Tooth Extraction; D014092:Tooth Root / Q000000981:diagnostic imaging; D014095:Tooth, Impacted / Q000000981:diagnostic imaging