ABSTRACT
Ideally, sealant is placed over caries-free pits and fissures, although evidence supports the view that sealing will lead to the arrest of early lesion. However, clinical examination of a pit or a fissure will often leave doubt as to its caries status. The present study compared the validity of three in-vivo methods of caries detection with the histological appearance of the sectioned teeth. A total of 48 sound teeth, planned to be extracted as part of arthodonctic treatment were included in the study. Teeth examined to score stains in the fissures, bitewing radiographs were taken, fissures were also examined by vanguard machine. Following extraction, teeth were examined histologically and photographed using polarized light. The results found no consistent pattern to correlate stain in the fissures with vanguard readings or with histological examinations. Radiographs were of limited value in diagnosis of occlusal caries and would not be indicated for clinical diagnosis. A sensitivity of 76% of the teeth showing histological signs of dimineralization gave positive vanguard readings. As for specificity, 90% of teeth on which no demineralization was found histologically gave zero vanguard reading