The comparison of cleaning efficacy and apical extrusion of advanced irrigation activation methods with a novel Er:YAG laser modality: sweeps

Abstract

Laser-activated irrigation (LAI) is an activation method that is based on transferring pulsed energy to the irrigation solution by using different fiber tips and generating explosive vapor bubbles with a secondary cavitation effect, causing rapid solution movement through the root canal. This study aimed to compare different types of LAI and ultrasonically activated irrigation (UAI) in terms of cleaning efficacy by using scanning electron microscopy (SEM) images. Sixty straight and single-rooted mature mandibular premolars were prepared with ProTaper Ni-Ti rotary instruments up to F4. According to the final irrigation/agitation protocols, four experimental groups (n = 15) were generated as conventional laser–activated irrigation (group 1: C.LAI), photon-induced photoacoustic streaming (group 2: PIPS), shock wave–enhanced emission photoacoustic streaming (group 3: SWEEPS), and passive ultrasonic irrigation (group 4:UAI). The irrigation protocols were performed for 60 s with 2.5% NaOCl and 17% EDTA. Debridement was evaluated using SEM with a scoring system. Apical extrusion was calculated using cube-shaped flower arrangement foam by subtracting the initial weights from the final weights. All data were statistically analyzed. C.LAI and SWEEPS showed significantly lower debris scores than PIPS and UAI (p < 0.001). However, there was no significant difference between C.LAI and SWEEPS. In the PIPS group, significantly more debris residue was found compared with the other groups. Apical extrusion was significantly lower in the PUI groups than in the laser-activated groups (C.LAI, PIPS, SWEEPS). There was no significant difference between laser-activated groups. It can be concluded that the use of the C. LAI and novel laser-activated irrigation modality (SWEEPS) provides greater cleaning efficacy compared to UAI and PIPS. Besides, the observed results should not be generalized to teeth with shorter or longer root length and smaller or larger canal preparation with immature root development and open apices. In teeth with resorption, perforation defects or immature roots with open apex, the higher amount of apical extrusion should also be taken into account.