An Innovative Application Of Thulium Fiber Laser In Endodontic Irrigation

This in vitro study evaluated the effectiveness and safety of an innovative application of 1940 nm thulium fiber laser (TFL) in endodontic irrigation. A pulsed 1940 nm thulium fiber laser (TFL) equipped with a 365 μm fiber was employed in this study. The generation of vapor bubbles in water was recorded via high-speed photography. Eight premolars were divided into four groups: TFL, Er:YAG laser, conventional needle irrigation, and a negative control group, to assess the efficacy of smear layer removal. Changes in root surface temperature were measured using a canine model, while transient apical peak pressure (TAPP) was quantified in a 3D-printed root canal model utilizing a high-frequency pressure sensor. Statistical analysis was conducted using a one-way analysis of variance (ANOVA). Optimal TFL parameters (10 mJ, 250 Hz, 2.5 W, SP mode) could generated vapor bubbles in water, achieving effective apical smear layer removal comparable to erbium laser. The TFL group exhibited marginally higher root surface temperature elevation (TFL: 3.34±0.20°C, Er:YAG: 1.15±0.11°C, p<0.05) but lower TAPP values (TFL: 4249.0±33.87 Pa, Er:YAG: 7856.7±24.31 Pa, p<0.05) than the erbium laser group. Thulium fiber laser (TFL) effectively generates vapor bubbles in water and removes the smear layer with 17% EDTA in endodontic irrigation, while ensuring safe apical pressure and minimal root surface temperature changes, making it a promising alternative for improved endodontic procedures.