Clinical vs Radiographic Extension of Class II Carious Lesions

Objectives: The aim of this in-vivo study was to compare a direct digital radiographic (DDR) system (RVG-6000) with the conventional bitewing radiograph (D-speed film) to estimate the axial extension of class II carious lesions. The patient's discomfort to placement of each radiographic packet was also evaluated. Methods: Fifty-one interproximal carious lesions in posterior teeth were utilized. The affected teeth were exposed to the Ultraspeed (D-speed) and the complementary metal oxide silicone (CMOS) based digital sensor (Kodak RVG-6000 size-2 sensor). The true caries depth was validated clinically from intra-operative photographs that captured the cross-sectional views of the lesion at its deepest point during the step wise dissection of the lesion. During the operative procedures the cavitation status was recorded. A 3 mm segment sectioned from the tip of a periodontal probe was placed on the occlusal surface of the decayed or adjacent tooth to act as a reference instrument before exposing the teeth to the radiographs or taking operative photographs. Two clinicians scored the radiographic images. The carious lesion extension from the dentino-enamel junction (DEJ) was measured from each radiograph in mm and the results were compared to the true clinical depth using One-way ANOVA and Tukey tests. Results: Both radiographs significantly underestimated the clinical depth (p<0.0001) with the RVG-6000 images being significantly closer to the actual depth of the lesion than the D-speed films (p=0.003). All of the lesions diagnosed radiographically to be deeper than 1 mm into dentin were cavitated. Size or sharp edges of the sensor caused the most patient discomfort (D-speed film, 64%; RVG-6000 sensor, 79%). Conclusions: Both radiographic images tend to underestimate the actual lesion extension. RVG-6000 digital images were more accurate in estimating interproximal lesion depth than D-speed radiographic images.