Discriminatory ability of caries diagnosis from bitewing radiographs in caries prophylactic trials

The discriminatory ability of radiological criteria in common use in clinical trials was tested on 99 female teenagers selected from a larger sample taking part in a 3-year caries prophylactic clinical trial. Four radiological caries diagnostic criteria were selected as generally representative of those in current use following a comprehensive review of the literature. A significant preventive effect was evident from the radiographic examination after 3 years. At this time a significant difference between mean DFS increments was recorded when enamel lesions were omitted (P smaller than 0.05). Although preventive treatment effects were evident at all diagnostic levels, the discriminatory abilities differed. The criterion "involvement of amelodentinal junction but not beyond" was most discriminatory.