title: A survey of the first 6 years of experience with cone beam CT scanning in a teaching hospital orthodontic department.
abstract: OBJECTIVE
  Cone beam computed tomography (CBCT) is a specialized form of radiography and has been used in the Glasgow Dental Hospital since 2006. The clinical notes of all patients referred for CBCT from the orthodontic department between 2006 and 2011 were evaluated to determine the reasons for referral, scan parameters and clinical findings.
  
  
  METHODS
  Retrospective observational study.
  
  
  METHODS
  From a general database, the notes of patients from the Orthodontic Department of Glasgow Dental Hospital & School referred for CBCT imaging, since the inception of the service (2006 through to 2011) were examined. Information was obtained from CBCT request forms, case notes and radiology reports.
  
  
  RESULTS
  During the chosen time period, 290 patients were referred for CBCT. Of these, 280 had clinical records that were available for investigation. Analysis showed approximately a third of scans were carried out within 4 weeks of referral. The smallest height of 4 cm was used for over a third of the scans investigated. Sixty-two per cent of the scans examined the maxilla only, 32% both jaws and 6% the mandible only. The two most common reasons for referral were to accurately determine the position of impacted teeth and to identify the presence of root resorption in relation to impacted teeth. In this cohort, 39% of teeth adjacent to an impacted tooth were found to have some root resorption, which closely supports the current literature.
  
  
  CONCLUSIONS
  This study provides a general overview of CBCT used by an orthodontic department in a teaching hospital environment.
authors.affiliation: L. M. Dobbyn, Orthodontic Department, Merlin Park University Hospital, Galway University Hospitals, Merlin Park, Galway, Ireland. lornadobbyn@hotmail.com
authors.forename: Lorna Mary
authors.initials: LM
authors.lastname: Dobbyn
authors.forename: Joanna Faye
authors.initials: JF
authors.lastname: Morrison
authors.forename: Laetitia Mary
authors.initials: LM
authors.lastname: Brocklebank
authors.forename: Lucy Lai-King
authors.initials: LL
authors.lastname: Chung
mesh_terms: D054893:Cone-Beam Computed Tomography / Q000706:statistics & numerical data*; D003796:Dental Service, Hospital; D006784:Hospitals, Teaching; D006801:Humans; D007568:Jaw / Q000000981:diagnostic imaging; D009970:Orthodontics; D012189:Retrospective Studies; D012391:Root Resorption / Q000000981:diagnostic imaging; D012606:Scotland