RESUMO
BACKGROUND: The diagnosis of approximal lesions is limited due to the difficulty of direct examination of these areas. AIM: To determine the accuracy of pen-type laser fluorescence (LFpen) device, compared to digital bitewing (BW) radiography, in diagnosing approximal carious lesions in posterior primary teeth at cavitation and non-cavitation thresholds. DESIGN: A total of 46 children (aged 3-9 years) were assessed and 195 approximal surfaces of 184 primary molars were examined by digital BW and LFpen. Visual-tactile inspection based on the International Caries Detection and Assessment System (ICDAS-II) was used as the reference standard. All examinations were performed by the same examiner. Sensitivity, specificity, and accuracy were calculated. Spearman's correlation coefficients were calculated between LFpen and BW readings and the reference standard. RESULTS: Sensitivity, specificity and AUC were 81.8, 86.7, and 0.84 for BW and 49.1, 87.9, and 0.69 for LFpen both at non-cavitation thresholds. At cavitation thresholds, BW showed higher specificity (96.0), sensitivity (93.0), and AUC (0.98) than did LFpen (72.0, 86.9, and 0.82, respectively), but a lower correlation was indicated by LFpen readings. CONCLUSION: Bitewing had a better diagnostic accuracy and significantly outperformed LFpen in the detection of non-cavitated lesions. Similar results were obtained by the two methods at the cavitation threshold.