Assessment of the Depth of Clinically Detected Approximal Caries Lesions Using Digital Imaging Fiber-Optic Transillumination in Comparison to Periapical Radiographs

OBJECTIVES: The aim of present prospective clinical trial was to assess the depth of clinically detected approximal caries lesions using digital imaging fiber-optic transillumination in comparison to periapical radiographs. MATERIAL AND METHODS: One calibrated examiner diagnosed 31 approximal carious lesions in 10 patients with a mean age of 21.8 (SD 1.1) years. The lesions were assessed using digital imaging fiber-optic transillumination (DIFOTI) and digital periapical radiographs (PA). Depending on the depth of the lesions, scores for demineralisation in PA (R) and DIFOTI (F) images were given by two examiners: R0/F0 - no demineralisation, R1/F1 - demineralisation confined to the outer half of the enamel, R2/F2 - into the inner half of the enamel, 3/3 - along the amelodentinal junction, R3/F3 - into the outer half of dentine, R4/F4 - into the inner part of the dentine. Spearman’s rank correlation coefficient and kappa were calculated. RESULTS: Spearman’s rank correlation coefficient between DIFOTI and PA was 0.031 (P > 0.05), kappa was 0.077. In 26% of the cases, DIFOTI showed higher scores of demineralisation, relative to PA. In 36% of the cases, PA showed higher scores of demineralisation than DIFOTI. PA showed demineralisation into the outer and inner half of the dentine in 89% of the cases with underlying shadow and in 70% of the cases with opacities. CONCLUSIONS: Digital imaging fibre optic transillumination and periapical radiographs produce evaluations of the depth of approximal caries lesions that do not match.