In vitro comparison of subjective image quality of the pana digital intraoral x-ray imaging system and conventional intraoral radiography in caries detection

Abstract

The aim of this study was to evaluate observer performance with a charge coupled device-based intraoral X-ray imaging system, Pana Digital system, in comparison with conventional film-based radiography (Ektaspeed Plus). A total of 118 teeth mounted in plaster were radiographed using both the Pana Digital system and conventional film. The occlusal and approximal surfaces of the resultant images were evaluated by six observers in relation to the caries depth. For the verification of the caries depth, the teeth surfaces were rated histologically by two examiners according to the same rating scores used for the X-ray imaging assessment. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of the two image modalities were calculated together with Cohen's kappa values. No significant difference was found in any diagnostic parameters at any thresholds between the two modalities. The Kappa values for the Pana Digital system showed relatively lower levels than those of conventional film in occlusal caries assessment, whereas no apparent differences were found between the two modalities in any scores of depth for approximal caries assessment. The results of the present study, in which there was no discrepancy in diagnostic abilities, suggested that the Pana Digital system could play a useful role in clinical caries diagnosis.