title: Intraoral versus extraoral bitewing radiography in detection of enamel proximal caries: an ex vivo study.
abstract: OBJECTIVE
  To compare the diagnostic accuracy of digital intraoral and extraoral bitewing (EO BW) radiography in the detection of enamel proximal caries regardless of their ability to separate contacts.
  
  
  METHODS
  Artificial caries with different degrees of decalcification was induced in 80 human sound premolars and molars using formic acid. Intraoral radiographs were taken with photostimulable phosphor plate (PSP) and complementary metal oxide semiconductor (CMOS), using the paralleling bitewing technique. Extraoral bitewing radiographs were obtained using Sirona digital panoramic X-ray unit (Sirona Siemens, Bensheim, Germany). In total, 160 proximal surfaces were assessed by 2 observers twice. Area under the receiver operating characteristic curve (Az) values for each image type, observer and reading were compared using z-tests, with a significance level of p ≤ 0.05. Sensitivity, specificity, positive-predictive value and negative-predictive value for each observer and reading were calculated.
  
  
  RESULTS
  Spearman's test showed a strong positive correlation between the duration of demineralization and histological grading of carious teeth surfaces. For the three radiographic techniques, intraobserver reliability was strong to excellent. Moreover, interobserver agreement was strong. The differences between all detection methods were not statistically significant (p > 0.05). Intraoral bitewing using CMOS sensor had the highest sensitivity while EO BW had the highest specificity in the detection of incipient proximal caries.
  
  
  CONCLUSIONS
  Within the limits of the ex vivo design, the difference in diagnostic accuracy between the three radiographic techniques was not significant. EO BW could be used in the detection of enamel proximal caries with results comparable with intraoral bitewing with PSP plate and CMOS sensor.
authors.affiliation: Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Ain Shams University, Cairo, Egypt.
authors.forename: Walaa Hussein
authors.initials: WH
authors.lastname: Abu El-Ela
authors.affiliation: Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Ain Shams University, Cairo, Egypt.
authors.forename: Mary Medhat
authors.initials: MM
authors.lastname: Farid
authors.affiliation: Department of Oral and Maxillofacial Radiology, Faculty of Dentistry, Ain Shams University, Cairo, Egypt.
authors.forename: Mostafa Saad El-Din
authors.initials: MS
authors.lastname: Mostafa
mesh_terms: D019540:Area Under Curve; D001641:Bicuspid / Q000000981:diagnostic imaging / Q000473:pathology; D003731:Dental Caries / Q000000981:diagnostic imaging* / Q000473:pathology; D003743:Dental Enamel / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008963:Molar / Q000000981:diagnostic imaging / Q000473:pathology; D015588:Observer Variation; D011237:Predictive Value of Tests; D012372:ROC Curve; D016300:Radiography, Bitewing / Q000295:instrumentation / Q000706:statistics & numerical data*; D019252:Radiography, Dental, Digital / Q000295:instrumentation / Q000706:statistics & numerical data; D011862:Radiography, Panoramic / Q000295:instrumentation / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity; D017001:Tooth Demineralization / Q000000981:diagnostic imaging / Q000473:pathology; D014963:X-Ray Intensifying Screens
keywords: bitewing; dental caries; digital; radiography