title: Audit of a 5-year radiographic protocol for assessment of mandibular third molars before surgical intervention.
abstract: OBJECTIVE
  To perform an audit of a three-step protocol for radiographic examination of mandibular third molars before surgery.
  
  
  METHODS
  1769 teeth underwent surgery. A standardized three-step radiographic protocol was followed: (1) panoramic imaging (PAN), (2) stereoscanography (SCAN) and (3) CBCT. If there was overprojection between the tooth and the canal in PAN, SCAN was performed. If the tooth was determined to be in close contact with the canal in SCAN, CBCT was performed. Close contact between the tooth and the canal was assessed in all images, and patient-reported sensory disturbances from the alveolar inferior nerve were recorded after surgery. The relation between the final radiographic examination and sensory disturbances was determined. Logistic regression analysis tested whether signs for a close contact in PAN/SCAN could predict no bony separation between the tooth and canal in CBCT.
  
  
  RESULTS
  46% of teeth underwent PAN, 31% underwent SCAN and 23% underwent CBCT as the final examination. 21% underwent all three radiographic examinations. 53/76% of teeth with close relation to the canal in PAN/SCAN showed no bony separation in CBCT; if there was close relation in PAN/SCAN, there was 1.6/4.3 times higher probability that no bony separation existed in CBCT. 16 cases of sensory disturbances were recorded: 4 operations were based on PAN, 8 on SCAN and 4 on CBCT.
  
  
  CONCLUSIONS
  The radiographic protocol was in general followed. SCAN was superior to PAN in predicting no bony separation between the tooth and the canal in CBCT, and there was no relation between sensory disturbances and radiographic method.
authors.affiliation: 1 Section of Oral Radiology, Department of Dentistry, Aarhus University, Aarhus, Denmark.
authors.forename: L H
authors.initials: LH
authors.lastname: Matzen
authors.forename: S
authors.initials: S
authors.lastname: Schou
authors.forename: J
authors.initials: J
authors.lastname: Christensen
authors.forename: H
authors.initials: H
authors.lastname: Hintze
authors.forename: A
authors.initials: A
authors.lastname: Wenzel
keywords: CBCT; molar third; radiology