Explaining the working mechanism of laser-activated irrigation and its action on microbial biofilms: A high-speed imaging study.

The hydrodynamic effect of LAI is based on the generation of small cavitation bubbles throughout the entire canal, far from the primary bubble. Their volumetric oscillation results in a small yet very fast vertical movement of the root canal content and local liquid streaming on each pulse, resulting in biofilm detachment and coronal displacement.