title: Variable-resolution cone-beam computerized tomography with enhancement filtration compared with intraoral photostimulable phosphor radiography in detection of transverse root fractures in an in vitro model.
abstract: OBJECTIVE
  The aim of this study was to compare the diagnostic accuracy of an intraoral photostimulable storage phosphor (PSP) plate system and cone-beam computerized tomography scanning (CBCT) for detection of experimentally induced transverse root fractures and to evaluate differences between original images and images enhanced with high-pass filters.
  
  
  METHODS
  Sixty-nine extracted human teeth, 34 with root fractures and 35 without, were examined under standardized conditions using an intraoral PSP system (Digora Optime; Soredex). The images were saved in original 8-bit format and in a version sharpened with a high-pass filter. The teeth were examined with CBCT (i-Cat; Imaging Sciences) in 2 resolutions: 0.125 mm and 0.25 mm voxel size. Original images were saved together with images enhanced with 2 high-pass filters, sharpen and angio-sharpen. Six observers scored the presence of a root fracture in all modalities in random order. Sensitivity, specificity, and accuracy [(true positives + true negatives)/all scores] were calculated for each modality and each observer. Differences were estimated by analyzing the binary data, assuming additive effects of observer and modality in a generalized linear model.
  
  
  RESULTS
  High-resolution original CBCT images had higher sensitivity (P < .05) than lower-resolution images and PSP images (0.125 mm resolution 87%, 0.25 mm resolution 72%, and PSP 74%). Angio-sharpen-filtered images for both CBCT resolutions had higher sensitivities (P < .02) than the original images (0.125 mm resolution: 95% vs. 87%; 0.25 mm resolution: 81% vs. 72%). There was no significant difference between the lower-resolution CBCT and PSP images. Only small differences in specificity were seen between modalities, and accuracy was higher for high-resolution CBCT than for the other modalities (P < .03).
  
  
  CONCLUSIONS
  High-resolution i-Cat CBCT images resulted in an increase in sensitivity without jeopardizing specificity for detection of transverse root fractures compared with lower-resolution CBCT images, which were not more accurate than periapical PSP images. The angio-sharpen high-pass filter improved sensitivity in the high-resolution CBCT images in this in vitro model.
authors.affiliation: Department of Oral Radiology, School of Dentistry, Faculty of Health Sciences, Aarhus University, Aarhus, Denmark. awenzel@odont.au.dk
authors.forename: Ann
authors.initials: A
authors.lastname: Wenzel
authors.forename: Fransisco
authors.initials: F
authors.lastname: Haiter-Neto
authors.forename: Morten
authors.initials: M
authors.lastname: Frydenberg
authors.forename: Lise-Lotte
authors.initials: LL
authors.lastname: Kirkevang
mesh_terms: D054893:Cone-Beam Computed Tomography; D006801:Humans; D011856:Radiographic Image Enhancement / Q000295:instrumentation / Q000379:methods*; D019252:Radiography, Dental, Digital / Q000295:instrumentation / Q000379:methods*; D012680:Sensitivity and Specificity; D014082:Tooth Fractures / Q000000981:diagnostic imaging* / Q000473:pathology; D014092:Tooth Root / Q000000981:diagnostic imaging* / Q000293:injuries / Q000473:pathology