Diagnostic Accuracy of Image Enhancement in Intra-Oral Direct Digital Radiography in the Assessment of Interproximal Caries

The first commercial system for digital radiography was introduced in 1987, and it has evolved a great deal since then. Currently, it is possible to enhance images in digital radiography. The aim of this study is to evaluate the diagnostic accuracy of image enhancement in direct digital radiography as it relates to interproximal carries assessment. Following extraction, 50 human teeth were kept in acidic gel (methyl cellulose + acetate buffer PH = 4.8) for 42 days at 37°C to cause caries before mounting. Direct digital radiography was then taken. Two filters were used: sharpen and emboss. Three radiologists evaluated the images with two weeks interval. The histologic assessments were gold standard. Additionally, SPSS 20 was used to draw an ROC curve and calculate AUC. Cohen’s kappa and interclass correlation coefficient (ICC) were used to measure intra- and inter-observer reliability. For the emboss filter, sensitivity was 95%, specificity was 100%, and accuracy was 96%. For the sharpen filter, sensitivity was 88%, specificity was 100%, and accuracy was 90%. Also, the AUC for the emboss filter was 0.97, and it was 0.94 for the sharpen filter. Cohen’s simple kappa was in the range of excellent. Using these filters in intra-oral direct digital radiography (especially the emboss filter) can help some clinicians to increase diagnostic accuracy in the assessment of inter proximal caries of posterior teeth.