Subjective Image Quality of Intra Oral Digital Radiography Systems

Objectives: This study was designed to examine the subjective aspect of image quality of intra oral digital radiographic systems. Methods: Visualix (CCD), VistaScan (PSP), Digora (PSP) and one conventional film were evaluated. A test object was made to examine subjective aspect of image quality. Two X-ray generators were operated at 60kV and 6mA and exposure times ranged from 0.01 to 2 seconds. Five observers were recruited to evaluate the images. Images from film were digitized and all images were displayed on a 17” monitor. Observer agreement in quality assessment was analysed using weighted kappa (Fleiss and Cohen) scores. Results: The result showed general substantial agreement between observers for all systems (&Kappa = 0.61 to 0.80) and moderate to almost perfect agreement (&Kappa =0.81 to1.0) were recorded for the intra observer assessments of image quality. VistaScan and Digora (PSP systems) offered a very wide latitude of exposure to produce diagnostically quality images. However the optimum image quality scores were recorded for Visualix (CCD system) over narrower latitude. Conclusions: There were marked differences in the imaging characteristics of the systems. Choice of digital system should be made after consideration of the image quality and the latitude.