Light-based therapies in dentistry: applications in cariology, endodontics, and periodontology

Light-based therapies are increasingly used in dentistry as adjunctive and minimally invasive tools. They support diagnosis, microbial reduction, tissue modulation, pain control and healing. This mini review summarizes their applications in cariology, endodontics and periodontology. The main modalities include dental lasers, antimicrobial photodynamic therapy, photoactivated disinfection and photobiomodulation. In cariology, light-based therapies assist in caries detection, selective caries removal, bacterial reduction, enamel and dentin modification, remineralisation support and dentin hypersensitivity management. However, most data are derived from in vitro or short-term clinical studies, and their long-term benefits over conventional preventive and restorative care remain unclear. In endodontics, laser-assisted irrigation and antimicrobial photodynamic therapy may improve root canal disinfection and biofilm disruption and may be helpful in managing persistent infections. However, differences in wavelengths, power settings, photosensitizers and clinical protocols limit standardisation. In periodontology, light-based therapies have been studied as adjuncts to scaling and root planing, peri-implant disease treatment, postoperative pain control and soft-tissue healing. Current evidence suggests short-term reductions in inflammation and microbial load, but clinical outcomes remain variable. Important limitations include unclear indications, variable dosimetry, thermal safety concerns, high cost and limited long-term clinical evidence. Standardised protocols and high-quality randomised clinical trials are needed. Future progress will depend on precise dosimetry, device standardisation, and improved understanding of light–tissue–microbe interactions. Overall, light-based therapies show promising potential in dentistry, with existing literature supporting their various applications and effects; however, substantial heterogeneity in study designs and treatment parameters precludes standardised recommendations.