Clinical and radiographic assessment of approximal carious lesions

The aim of the study was to compare the radiographic diagnosis of approximal carious lesions with visual observations of the approximal surfaces and within drilled Class II cavities (made into the pulp). Sound (n = 28) and carious (n = 123) approximal surfaces of extracted premolars and molars were radiographed. The radiographs were studied by seven observers to diagnose caries. Lesions without cavitation were most often classified as sound (61.3%). When lesions had cavities, the rate of detection increased to 89.1%. Sound surfaces were erroneously classified as carious in 15.7% of cases. Statistically, about 6 out of every 10 qualitative assessments of lesion depth on the basis of radiographs correctly recorded lesions as being in enamel or extending into dentin. The interexaminer variation in radiographic caries diagnoses were mostly due to difference in diagnostic criteria, whereas differences in diagnostic capability were less important.