Visual-tactile examination compared with conventional radiography,digital radiography,and Diagnodent in the diagnosis of occlusal occult caries in extracted premolars

PURPOSE: This laboratory study compared visual-tactile examination with conventional radiographs, digital radiographs, and laser fluorescence in the detection of occlusal occult caries on extracted premolar teeth. METHODS: Extracted premolars without obvious caries or restorations were collected from school dental clinics. Occlusal surfaces of 320 extracted premolars were examined visually with an explorer, then examined using the KaVo Diagnodent unit and scored using specific criteria. The teeth were exposed using conventional and digital radiography, respectively. The radiographs were assessed for dentin radiolucencies beneath the occlusal surface. RESULTS: Of the 320 teeth used in this study, 302 were scored as sound by visual-tactile examination. Of these, 57 (19%) demonstrated dentin radiolucency on conventional bite-wings, and 245 (81%) were scored as radiographically sound. Thus, the sensitivity and specificity values of the visual-tactile examination compared with conventional radiography were 81% and 44%, respectively. In contrast, Diagnodent produced results of 82% sensitivity and 36% specificity when compared with conventional radiography. When compared to digital radiography, the sensitivity and specificity values of the visual-tactile examination were 90% and 44%, respectively. In contrast, when compared to digital radiography, Diagnodent showed a very low specificity of only 32%, although sensitivity was still high at 91%. Differences in specificity among the techniques were statistically significant (P < .03), whereas differences in sensitivity were not (P > .01). CONCLUSIONS: Although the diagnosis of occult dentinal caries may be further enhanced by the Diagnodent, a combination of visual-tactile examination and either conventional or digital radiography should identify over 80% of lesions.