Comment on "Direct radiation damage to human tooth under IMRT for head and neck cancer" by Tamahara and Kouketsu.

We found the article by Tamahara and Kouketsu (Radiat Environ Biophys 2025. https://doi.org/10.1007/s00411-025-01180-w ) interesting because it examined the direct physicochemical effects of therapeutic irradiation on human dental hard tissues as a possible non-salivary cause of radiation-related caries (RRC). The authors investigate a clinically significant and mechanistically fascinating question, utilizing a controlled in vitro approach to analyze radiation-induced modifications in enamel and dentin. The research provides comprehensive information on microhardness, calcium release, collagen autofluorescence, and localized pH variations following irradiation. Nonetheless, specific methodological and interpretation concerns significantly impact the robustness and breadth of the authors’ conclusions, necessitating further scrutiny.