Histologic validation of ICDAS ‐ II and polarization sensitive optical coherence tomography to detect smooth surface early carious lesions

Aim This in vitro study aimed to histologically validate and compare the methods for detection of smooth surface early carious lesions ( ECL s) that is , International caries detection and assessment system for the smooth surface ( ICDAS ‐ II ‐ SSC ), Polarization sensitive optical coherence tomography ( PS ‐ OCT ), and radiography. Methodology PS ‐ OCT images for scores 0‐3 of ICDAS ‐ II ‐ SSC were standardized according to ECL s’ depth. Preliminary PS ‐ OCT images for ICDAS ‐ II ‐ SSC score‐2 of pigmented ECL s showed reduced lesion depth and therefore were dichotomized into scores 2 and 2p for white and pigmented lesions ( ICDAS ‐ II ‐ SSC m). ECL s on one hundred freshly extracted teeth were scored by three examiners for ICDAS ‐ II ‐ SSC m, PS ‐ OCT , radiography, and histology. Results Compared to histology, ICDAS ‐ II ‐ SSC m showed a strong positive correlation followed by PS ‐ OCT and radiographic evaluation. ICDAS ‐ II ‐ SSC m had a strong positive correlation with PS ‐ OCT , while both variables had a weak positive correlation with radiography. PS ‐ OCT detected the activity of ECL s by directly relating the image depth of ECL s to their mineral volume content. Conclusion The current scope of ICDAS ‐ II should be reviewed since the pigmentation can be misinterpreted as an active lesion. Till then, ICDAS ‐ II ‐ SSC is an effective visual method for early caries detection. PS ‐ OCT has the potential to become a probe with the proper algorithm for diagnostic purposes.