Relationship between Histological and Radiographic Caries Lesion Depth Measured in Images from Four Digital Radiography Systems

Abstract

The aim of this study was to compare the accuracy of approximal caries lesion depth measurements in radiographs from four digital systems. Two CCD-based sensors, Dixi (Planmeca) and Sidexis (Sirona), and two phosphor plate systems, Digora (Soredex) and DenOptix (Gendex), were used to record radiographs of 177 extracted human teeth. Sixty-four radiographically visible lesions were selected and measured by 4 observers in the digital radiographs and in digital photographs of histological sections of the teeth. The gold standard (true measure) was defined as the mean of the 4 observers’ measurements on the histological sections. Two untrained observers underestimated general lesion depth in all the radiographic systems while each of 2 trained observers underestimated the depth in one of the systems. Analysis of variance revealed that Digora images resulted overall in the smallest underestimation, followed by Dixi, DenOptix and Sidexis. The differences between Digora and Sidexis and between Dixi and Sidexis were statistically significant (p < 0.05). Analysis of variance using the regression coefficient as the test variable demonstrated that the coefficients differed between DenOptix and the remaining systems (p < 0.05) while there were no significant differences between these (p > 0.05). It can be concluded that radiographs obtained with the Dixi and Digora systems were more accurate than Sidexis and DenOptix images for measurement of caries lesion depth. Still, a high probability exists that the individual lesion measurement is either overestimated or underestimated compared to the true lesion depth.

Performance of a photostimulable storage phosphor digital system with or without the sharpen filter and cone beam CT for detecting approximal enamel subsurface demineralization

“…4,5 Radiographic examination is widely used and easy to perform for the diagnosis of approximal caries. [5][6][7][8][9] In the early 1990s, digital radiographic systems were launched, yielding the great possibility of manipulating image brightness and contrast to improve diagnosis. 10 Nevertheless, the radiographic diagnosis of caries lesions depends on the contrast and, therefore, demineralization has to encompass at least 30-40% of the enamel layer to be observed, implying an irreversible mineral loss.…”

Comparison of digital systems and conventional dental film for the detection of approximal enamel caries

“…Several studies have shown that direct digital systems have a number of advantages when compared with conventional film. 2,[7][8][9][10][11][12][13] For example, the exposure dose should, in principle, be reduced since digital images are less likely to show the high frequency of exposure or processing artefacts often experienced with conventional film; working time from image exposure to image display is reduced (no wet processing is involved) and image communication is easier. Another potential advantage of digital imaging is the ability to perform image quality enhancements such as contrast and density modulation, which may increase diagnostic accuracy.…”

Comparison of digital and conventional radiographic techniques

“…Still, the digital method has other advantages such as: the elimination of the chemical developing process, the immediate availability of the image, the image enhancement function (mostly changes of density and contrast), the small storage space needed, the use in teleradiology, the availability in multiple reprints, and the lower contamination of the environment [11,13,21,28].…”