title: Detection of bone invasion by gingival carcinoma of the mandible: a comparison of intraoral and panoramic radiography and computed tomography.
abstract: OBJECTIVE
  To assess the diagnostic accuracy of panoramic radiography (PR), panoramic radiography combined with intraoral radiography (PR+IR), and CT in detecting the supero-inferior extent of tumor invasion of the mandible by gingival carcinoma.
  
  
  METHODS
  PR, PR+IR, and CT images of the mandible in 37 patients with gingival carcinoma were evaluated by five oral radiologists for the supero-inferior extent of bone invasion using ROC analysis. The mean ROC curve area (Az) of each observer for the different imaging modalities was analysed by nonparametric two-way ANOVA. P<0.05 was considered statistically significant.
  
  
  RESULTS
  The mean Az for the detection of bone invasion were 0.88+/-0.03 for PR, 0.77+/-0.12 for PR+IR, and 0.87+/-0.03 for CT (P=0.0907). The mean Az for the detection of bone invasion beyond the alveolus was 0.89+/-0.07 for PR, 0.85+/-0.08 for PR+IR, and 0.83+/-0.06 for CT (P=0.5438). The mean Az for the detection of bone invasion beneath the mandibular canal were 0.94+/-0.04 for PR, 0.94+/-0.02 for PR+IR, and 0.91+/-0. 04 for CT (P=0.2466). No statistically significant differences were observed in Az between PR, PR+IR, and CT.
  
  
  CONCLUSIONS
  We consider that PR+IR should be adopted as the initial imaging modality to determine the extent of supero-inferior invasion of the mandible in gingival carcinoma.
authors.affiliation: Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Kyushu University, Fukuoka, Japan.
authors.forename: E
authors.initials: E
authors.lastname: Nakayama
authors.forename: K
authors.initials: K
authors.lastname: Yoshiura
authors.forename: K
authors.initials: K
authors.lastname: Yuasa
authors.forename: O
authors.initials: O
authors.lastname: Tabata
authors.forename: K
authors.initials: K
authors.lastname: Araki
authors.forename: S
authors.initials: S
authors.lastname: Kanda
authors.forename: S
authors.initials: S
authors.lastname: Ozeki
authors.forename: M
authors.initials: M
authors.lastname: Shinohara
mesh_terms: D000704:Analysis of Variance; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000473:pathology*; D005887:Gingival Neoplasms / Q000473:pathology*; D006801:Humans; D008339:Mandibular Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D009361:Neoplasm Invasiveness / Q000000981:diagnostic imaging*; D023861:Photography, Dental; D012372:ROC Curve; D011862:Radiography, Panoramic; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed