INTRAORAL STORAGE PHOSPHOR RADIOGRAPHY FOR APPROXIMAL CARIES DETECTION AND EFFECT OF IMAGE MAGNIFICATION - COMPARISON WITH CONVENTIONAL RADIOGRAPHY

Objectives. The aim of this study was first to test the newly develope d storage phosphor (SP) system Digora for diagnostic accuracy of appro ximal caries detection with Special emphasis on image magnification co mpared with conventional radiography, and second, to test whether the image surroundings could have an influence on observer performance. De sign. SP plates and Ektaspeed films were exposed simultaneously to 50 extracted premolars/molars, and the SP image files were transported to a different platform for processing. Ten observers rated 95 approxima l surfaces for caries with four imaging modalities: (1) SP images at d ental film size viewed with black surroundings, (2) magnified (x4) ima ges viewed in the same manner, (3) magnified (x4) images viewed with t ext and graphics framing, and (1) films viewed on a light box. The obs ervations were validated with microscopy. Diagnostic accuracy was calc ulated as the area beneath the receiver operating characteristic curve (A(z)). Results. No significant differences were found between SP ima ges and films. Magnified SP images with text and graphics demonstrated significantly higher A(z) values than nonmagnified images both for en amel and dentin, and magnified images with black surroundings demonstr ated similar results for dentin. Conclusions. In this in vitro materia l the observer performance for approximal caries detection with SP ima ges was comparable to that with Ektaspeed films. The magnified SP imag es generally showed a significantly higher diagnostic accuracy than th e nonmagnified SP images.