Evaluation of digital camera resolution in proximal caries detection

Abstract

The aim of this study is to evaluate the diagnostic acuuracy of proximal caries detection from digitized film images captured by digital camera at three different resolution setting. Methods: In an interventional and descriptive study that performed on radiography of molar and premolar teeth for detection of proximal caries, digital camera resolution in proximal caries detection evaluated. Twenty five periapical radiographes of 50 Premolar and 25 Molar teeth were photographed using a digital Camera, Olympus E 300 , at three different resolution setting: 640&480 , 960*1280, and 1200*1600 . seventy five digital images were transfereed to a computer , saved and opened using Adobe photoshop software .In addition, powerpoint slide was made from each digital image. 3 observers scored three groups of images(the films,the displayed 1:1 digital images on the Adobe photoshop software ,and the powerpoint slide) for the existence of proximal caries and the depth of caries. Ground section of the teeth were used as a E?golden standard . A(z) values under the Roc curve of each group of images and at different resolution were compared using the Fridmann and Wilcoxon signed rank tests. Results: Films showed the highest A(z) values. only the 1280*960 images on the Adobe photoshop software showed no significant differences of the A(z) values from the film. the digital images of three resolution setting of the powerpoint software showed no significant differences. for caries depth the 1280*960 images showed the lower values of mean differences in enamel lesions compared with the other two resolution group. Conclusion: In our study, although three used resolution for digital pictures had sufficient accuracy in diction proximal caries but pictures with resolution 1280*960 had highest agreement with radiological films in detection proximal caries. In order to digitized conventional films , it was no necessary to use the highest camera resolution setting to achieve high diagnostic accuracy for proximal caries detection.