Occlusal caries detection and quantification by DIAGNOdent and Electronic Caries Monitor: in vitro comparison

The Electronic Caries Monitor (ECM) and the recently introduced laser-based KaVo DIAGNOdent have been developed as clinical diagnostic aids in the detection and quantification of occlusal carious lesions. The aim of this in vitro study was to compare their reproducibility and validity. The ability of DIAGNOdent to retrieve sites of occlusal carious lesions without reference to photographs or drawings from previous assessments was also tested. The material comprised 87 premolar teeth: the occlusal surfaces were sound or exhibited non-cavity carious lesions of varying severity. All were photographed and measured by DIAGNOdent and ECM on 2 occasions, 2 weeks apart. The teeth were then sectioned into 300 microm thick slices. Two observers independently classified the sections according to the histopathology, into 5 categories, ranging from sound to dentinal caries in the inner part of the dentin. Statistical analysis comprised intra-class correlation coefficients (ICC) to test reproducibility and regression analysis of validity. Sensitivity and specificity were also calculated for detection of D3 lesions for both devices. DIAGNOdent recorded maximum readings at identical sites on both occasions in 89% of the teeth. The ICC for readings on 2 separate occasions was 0.97 for DIAGNOdent and 0.71 for ECM. The correlations with histology were r = 0.93 and 0.83, for DIAGNOdent and ECM, respectively. For detection of D3 lesions, the sensitivity and specificity were 0.8 and 1 for DIAGNOdent and 0.75 and 0.88 for ECM. In this in vitro study, DIAGNOdent was superior to ECM for occlusal caries detection.