OBJECTIVES: This systematic review analyzed studies concerning the effectiveness of Optical Coherence Tomography (OCT) in detecting and monitoring dental caries in enamel and dentin. DATA: Studies comparing the diagnostic accuracy of OCT in diagnosing caries clinically or using extracted teeth were included. SOURCES: Databases, including PubMed/MEDLINE, Web of Science, EMBASE, and Scopus were searched for clinical trials and studies conducted using human teeth between 2010 and 2024. The process of study selection and data extraction followed the PRISMA guidelines. The methodological quality of the included studies was evaluated using the Critical Appraisal Skills Programme (CASP) diagnostic study checklist. STUDY SELECTION: Seven studies met the inclusion criteria out of 1,266 articles identified. OCT modalities used in these studies include Cross-polarization OCT (CP-OCT), Swept-source OCT (SS-OCT), and polarization-sensitive (PS-OCT), with wavelengths ranging between 1310-1330 nm
axial resolutions were between 7.5-22 μm. SS-OCT had a high sensitivity of 74.1% and specificity of 95.7% when applied to caries detection. CP-OCT was able to identify dentin-penetrating lesions with greater accuracy than conventional radiography. There were strong correlations in the OCT measurements with the established diagnostic gold standards: polarized light microscopy (PLM), r=0.63, P<
0.01
transverse microradiography (TMR), r=0.75, P<
0.001. CONCLUSION: OCT has demonstrated better performance regarding early caries detection and its activity compared with traditional diagnostic methods. However, standardization of the imaging protocol and further larger clinical trials are required. CLINICAL SIGNIFICANCE: OCT offers significant clinical advantages in the diagnosis of dental caries. This technology enables early detection of carious lesions, facilitating timely intervention and potentially preserving tooth integrity. Investigating the clinical effectiveness of OCT is crucial to validate its utility in dental practice and to establish standardized protocols for its implementation in caries diagnosis.