To investigate the efficacy of a new
laser irrigation activation system [
shock wave-enhanced emission photo-acoustic streaming (SWEEPS)] in terms of
postoperative pain after primary root canal treatment compared with other techniques, namely photon-induced photo-acoustic streaming (PIPS), sonic system with EDDY, passive ultrasonic system (PUI), and manual dynamic activation (MDA). Two hundred patients with symptomatic irreversible
pulpitis in mandibular premolar teeth were enrolled and randomly allocated to five different irrigation activation groups (n = 40) after chemo-mechanical
root canal preparation. For irrigation activation, the SWEEPS and PIPS
tips were attached to the
Er-YAG laser system in the respective groups, while the Irrisafe tip was used in the PUI group and the EDDY tip in the sonic group. In the MDA group, irrigation was agitated with the master
gutta-percha cone. At postoperative hours 8, 24, and 48 and on day 7,
pain intensity was evaluated using the 10-mm Visual Analog Scale (VAS) and
analgesic intake was recorded. The Kruskal-Wallis test was used to analyze the VAS scores, and
pain prevalence and
analgesic intake were examined with the Pearson's chi-square test at the 5% significance level. The PIPS and SWEEPS groups had the lowest level and prevalence of
pain when compared to the remaining groups (P < 0.001). The PUI, sonic and MDA groups did not differ in terms of
pain scores at hours 8 and 48 (P > 0.05). On day 7, the highest score and
pain prevalence were recorded in the MDA group (P < 0.001). There was no difference between the groups in terms of
analgesic intake (P > 0.05).
Laser-activated irrigation systems provided lower
postoperative pain scores and levels compared to the other activation systems. The MDA group had the highest
pain scores and incidence at the end of the seventh day.