Keywords
Laser adjunctive therapy
Erbium Laser
Fluid dynamics
Infection control
Submitted : 2025-04-02
Accepted : 2025-04-17
Published : 2025-05-02
Abstract
Microbial infection is a principal etiological factor in pulp and periapical diseases, necessitating effective root canal therapy (RCT) for thorough decontamination of the root canal system. However, conventional mechanical and chemical preparation methods remain inadequate, often leaving significant portions of the canal uncleaned and contributing to persistent infection. The advent of erbium laser-assisted chemical preparation has demonstrated significant potential in enhancing root canal disinfection through advanced fluid dynamics mechanisms, particularly cavitation and photoacoustic streaming. This review explores the fundamental principles governing fluid dynamics in erbium laser-assisted irrigation, with a focus on primary and secondary cavitation effects. The interaction between erbium laser energy and water generates vapor bubbles that induce dynamic fluid movement, enhancing the penetration and distribution of irrigants deep within the root canal system. Key factors influencing fluid dynamics intensity, including laser parameters, working tip design, and water medium confinement, are critically analyzed. Furthermore, recent advancements such as Photon-Initiated Photoacoustic Streaming (PIPS), Photoacoustic Synchronized Transients (PHAST), and Shock Wave Enhanced Emission Photoacoustic Streaming (SWEEPS) are reviewed in the context of their ability to improve fluid motion and irrigation efficacy. While these laser-assisted techniques offer promising improvements over traditional methods, challenges remain in optimizing energy parameters and mitigating the constraints imposed by confined root canal environments. Future research should focus on refining fluid dynamics models and conducting clinical studies to validate the efficacy of these innovations. This review aims to provide a comprehensive overview of current developments in fluid dynamics research related to erbium laser-assisted chemical preparation, offering insights into its potential as an advanced modality for root canal disinfection.
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