Cancer Risk Estimation and Radiation-Protective Shielding in Dental Cone-Beam Computed Tomography: An Updated Narrative Review

Cone-beam computed tomography (CBCT) is widely used in dentomaxillofacial imaging, but its expanding use requires cautious appraisal of stochastic risk and dose optimization. This updated structured narrative review summarizes evidence on organ dose, effective dose, modeled cancer-risk estimation, cumulative exposure, diagnostic reference levels, and patient shielding in dental CBCT. PubMed/MEDLINE and Scopus searches were updated to 15 May 2026. Overall, 24 primary studies were synthesized: 9 addressing dose, diagnostic reference levels, cumulative exposure, or cancer-risk modeling, and 15 evaluating shielding or radiation-protection strategies. Dose and modeled risk varied markedly according to scanner type, field of view, exposure parameters, anatomical region, age, sex, and repeat imaging. The salivary glands, oral mucosa, thyroid, and eye lens were the most relevant exposed organs; children, female patients, and patients undergoing repeated imaging represented the most vulnerable groups. Shielding studies reported substantial dose reductions in selected protocols, but the benefit depended on shield design, positioning, field of view, and image-quality impact. Dental CBCT should be prescribed only when three-dimensional information is expected to change management and should be optimized through the smallest adequate field of view, low-dose protocols, cumulative-dose awareness, and selective shielding when diagnostically appropriate.