This prospective cohort study investigated the distribution pattern of carious lesions diagnosed by visual tactile and radiographic examinations, assessed the radiographic yield for clinical caries diagnosis, and estimated how accurately commonly used indicators for caries identified young adults who would benefit from radiographs at different thresholds. Overall, 576 patients aged 16-32 years seeking a first consultation were included. Patients were examined for caries and answered a validated questionnaire on sociodemographics and oral health behavior. Almost 10% of clinically sound approximal surfaces presented radiolucency in enamel/dentine. Of the clinically diagnosed noncavitated approximal and occlusal lesions, 22.5 and 17.7%, respectively, presented radiolucency reaching dentine at the radiographic examination. Noncavitated/enamel lesions detected radiographically were mainly at approximal surfaces (73.2%), while at occlusal surfaces these were negligible (0.7%). More than half of approximal dentine lesions were only detected radiographically (61.3%), while more than half of occlusal dentine lesions were only clinically diagnosed (57.1%). The hierarchical logistic regression analysis showed that patient's caries activity, D1MFS scores ≥17, and frequent consumption of soft drinks were significantly associated with detection of approximal enamel/dentine lesions. Also, patient's caries activity and frequent consumption of soft drinks were significantly associated with occlusal dentine caries (p ≤ 0.05). The indicator power of grouping these indicators as a predictor for the presence of radiographically detected lesions showed high sensitivity (0.84-0.91) and moderate specificity (0.64-0.73) for all surfaces and thresholds tested. In conclusion, radiographs increased significantly the number of approximal enamel/dentine and occlusal dentine lesions diagnosed. The ability to identify young adults with approximal lesions from the predictor was satisfactory. Bearing in mind that an essential contribution of bitewing radiographs to clinical examination is the detection of approximal noncavitated/enamel lesions that can be inactivated by nonoperative interventions, our results support the prescription of radiographs in young adults seeking a first consultation. Updating of current guidelines' recommendation of radiographs is warranted.