Extraoral imaging for proximal caries detection: Bitewings vs scanogram.
OBJECTIVE
The objective of this study was to compare the diagnostic accuracy of 3 extraoral imaging modalities with an intraoral bitewing radiograph for proximal caries detection.


METHODS
Three modalities of Cranex TOME scanograms, x-ray film and DenOptix photostimulable phosphor plates with and without digital enhancement, were compared with Insight intraoral radiographs for proximal caries detection. Nine observers evaluated images of the proximal surfaces of 45 extracted posterior teeth. The presence or absence of caries was scored using a 5-point confidence scale. The ground truth was determined from histological sections. Responses were evaluated by repeated measures analysis of variance (ANOVA) for areas under receiver operating characteristic (ROC) curves (A z ).


RESULTS
Repeated measures ANOVA (at alpha = 0.05) demonstrated significant differences among modalities ( P = .041). Paired t tests with Bonferroni correction demonstrated that Insight was superior to only unenhanced digital scanograms ( P = .003). Mean A z scores (+/-SD) were 0.73 (+/-0.08) for Insight, 0.65 (+/-0.06) for screen/film scanogram, 0.64 (+/-0.04) for unenhanced digital scanogram, and 0.66 (+/-0.07) for enhanced digital scanogram.


CONCLUSIONS
The performances of film-based and enhanced digital scanograms were not statistically different from Insight film for proximal caries detection. Unenhanced digital scanograms exhibited a statistically significant lower diagnostic accuracy than Insight film.
Khan
Emad A
EA
King Abdulaziz University, Faculty of Dentistry, Jeddah, Saudi Arabia. khane@dentistry.unc.edu
Tyndall
Donald A
DA
Caplan
Daniel
D
D000704:Analysis of Variance; D019540:Area Under Curve; D001641:Bicuspid / Q000000981:diagnostic imaging / Q000473:pathology; D003731:Dental Caries / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D016555:Matched-Pair Analysis; D008963:Molar / Q000000981:diagnostic imaging / Q000473:pathology; D015588:Observer Variation; D012372:ROC Curve; D011856:Radiographic Image Enhancement / Q000379:methods; D016300:Radiography, Bitewing / Q000706:statistics & numerical data; D019252:Radiography, Dental, Digital / Q000706:statistics & numerical data; D014962:X-Ray Film; D014963:X-Ray Intensifying Screens