Damir Snjaric: Apical Irrigant Extrusion During Laser Activated Irrigation Compared to Conventional Endodontic Irrigation Regimens
Background: Endo-irrigation is essential to mechanical shaping during root canal therapy. The complexity of the endodontic system, as well as the limited efficiency of endo-files, led to demand for more efficient and secure means of chemical processing. The application of Er:YAG laser and its cavitation phenomena during Laser-Activated Irrigation (LAI) became a new standard in endodontics, but there is lack of studies regarding possible apical irrigant extrusion.
Methods: Human upper incisor root canals (N=20) were instrumented to ISO 40, taper 0.06. Four different endodontic irrigation needles, two notched open-end and two side-vented (each type at 27G and 30G diameter) were put 2 mm short of the working length (WL), and constant NaOCl 3% flow rates (FR) of 0.05 and 0.1 ml/s were supplied by precision syringe pump. A special setup was used to provide a fixed position of the irrigation system elements. Three different fiber tips (PIPS, Xpulse and Preciso) were also used, with the Er:YAG laser set at 10 mJ/15 Hz for LAI with 0.1 ml/s of irrigant supplied at the level of the pulp chamber. Each irrigation regimen was performed (N=10) for 60 s and the weight of apically extruded irrigant was measured.
Results: The notched open-end 27G needle at FR 0.1 ml/s showed the highest mass of extruded irrigant (MV 2.18 g) while LAI with PIPS showed the lowest (MV 0.16 g). All LAI regimens showed lower apical extrusion compared to conventional irrigation methods.
Conclusion: The low apical extrusion of LAI, measured in this pilot study, provides evidence which strongly supports the application of Er:YAG laser in endo-irrigation.
