Lasers as a Therapeutic Tool in Endodontics: Mechanisms, Clinical Applications, and Current Evidence — A Comprehensive Review

Abstract

Successful endodontic therapy depends on effective microbial elimination from the complex root canal system and prevention of reinfection. Despite advancements in chemomechanical preparation, conventional instrumentation and irrigation techniques exhibit limitations in accessing intricate canal anatomy and achieving complete disinfection. In recent years, laser technology has emerged as a promising adjunctive tool in endodontics due to its unique photothermal, photochemical, and photoacoustic properties.

This narrative review evaluates the mechanisms of action, therapeutic applications, advantages, and limitations of commonly used laser systems in endodontics, including diode, Nd:YAG, Er:YAG, Er,Cr:YSGG, and CO₂ lasers. Applications discussed include root canal disinfection, smear layer removal, laser-activated irrigation, photodynamic therapy, vital pulp therapy, postoperative pain control, and enhancement of periapical healing. Evidence suggests that erbium-based lasers are particularly effective for irrigant activation and smear layer removal, whereas diode and Nd:YAG lasers demonstrate deeper dentinal penetration and enhanced antimicrobial effects. Low-level laser therapy has shown potential in modulating inflammation and reducing postoperative discomfort.

Although encouraging results have been reported, variability in clinical protocols, concerns regarding thermal safety, and the absence of standardized guidelines limit widespread adoption. Current evidence supports the role of lasers as adjunctive modalities that enhance conventional endodontic procedures rather than replace them. Further well-designed clinical trials are required to establish standardized protocols and long-term clinical outcomes.