title: High resolution charge-coupled device sensor vs. medium resolution photostimulable phosphor plate digital receptors for detection of root fractures in vitro.
abstract: The aim of this study was to compare the diagnostic accuracy of a high resolution charge-coupled device (CCD) sensor and a medium resolution photostimulable phosphor (PSP) plate for detecting experimentally induced root fractures and further, to evaluate differences between images taken with various horizontal and vertical angles. Forty-seven extracted single-rooted human teeth mounted in a dry human skull were used in the experiment. The teeth were radiographed, before and after root fractures were induced, with two digital receptors: the Digora PSP system (approx. 8 lp mm(-1)) and the RVG-ui(TM), a CCD sensor with a high-resolution mode (15-20 lp mm(-1)). Four images were taken with each of the receptors of each tooth: one orthogonal exposure (O-images), one exposure with a vertical angle of 15 degrees by which the root was imaged elongated (L-images), and two eccentric exposures with a horizontal angle of 15 degrees mesially and distally. Three observers marked a fracture line if detected, in each image. Three sessions were held, one assessing the O-images, one the L-images, and one in which all four images of the same tooth were displayed simultaneously (X-images). The RVG-ui images obtained higher sensitivities than the Digora PSP images (P <0.05). Sensitivity was statistically significantly higher for the X-images than for both the O-images and the L-images (P <0.05). Based on the observed means, specificities were significantly different neither between the angles, nor between the images from the two digital systems taken with the same angle (P >0.05). It may be speculated that the difference in spatial resolution between the two digital systems accounts for the differences in their sensitivity.
authors.affiliation: Department of Oral Radiology, Royal Dental College, Faculty of Health Sciences, University of Aarhus, Aarhus, Denmark. awenzel@odont.au.dk
authors.forename: Ann
authors.initials: A
authors.lastname: Wenzel
authors.forename: Lise-Lotte
authors.initials: LL
authors.lastname: Kirkevang
mesh_terms: D000704:Analysis of Variance; D006801:Humans; D015588:Observer Variation; D019252:Radiography, Dental, Digital / Q000295:instrumentation*; D015203:Reproducibility of Results; D012666:Semiconductors; D012680:Sensitivity and Specificity; D014082:Tooth Fractures / Q000000981:diagnostic imaging*; D014092:Tooth Root / Q000000981:diagnostic imaging / Q000293:injuries*; D014159:Transducers