Diagnostic accuracy of image enhancement in intra-oral direct digital radiographs on assessment of inter proximal caries

Abstract

Film based radiography is slowly replaced by digital radiography. Many causes have led film to digital systems. It is possible to enhance image in digital radiography. Several studies have shown benefits of this, despite other studies have shown less or non effect. Diagnosis of loosing little mineral material in initial defects to active is often difficult in radiography, because proximal areas of posterior teeth are often extended. Aim: Evaluation of diagnostic accuracy of image enhancement in direct digital radiography for inter proximal caries assessment. Material & methods: Fifty human extracted teeth were kept at acidic gel (methyl cellulose + acetate buffer PH=4.8) for 42 days and 37 C to cause caries, each three teeth were mounted. Direct digital radiography by KODAK S800-USA was taken, film to object distance was 0.5cm to imitate intra oral condition. two filters were used by KODAK's specific program: Sharpen, Emboss. Three radiologists saw images. They evaluated images two weeks later again. Histological assessment was Gold standard. ROC curve (receiver operating characteris) was used to compare diagnostic accuracy of these filters. AUC (Area under curve) means Az, was analyzed to compare ROC curves. We used Cohen's simple K for intra & inter observer agreement. SPSS was used at all analysis. Results: For Emboss filter sensitivity is %95, specifity %100, and accuracy % 96. For Sharpen filter sensitivity is %88, spesifity %100, and accuracy % 90. Cohens Simple K - intra & inter observer- is excellent. Conclusion: These filters especially emboss- can improve diagnostic accuracy on assessment of inter proximal caries of posterior teeth. Using of these filters in intra-oral direct digital radiographs can help some clinicians to increase diagnostic accuracy on assessment of inter proximal caries of posterior teeth.