Investigating the effect of low-level laser in controlling gag reflex during periapical radiography preparation

Abstract

Purpose: The gag reflex can occur in some individuals during the preparation of intraoral radiography. The aim of this study was to investigate the effect of photobiomodulation therapy for controlling it. Methods: This clinical trial study included 26 patients who had severe gag reflexes during intraoral radiography. Patients were randomly assigned to two equal groups: one treated with a photobiomodulation therapy (diode 660 nm, 50 mW, 3 J/cm2, CW, on PC-6 point), another group had similar method but laser was off. The gag reflex intensity was measured using the Visual Analog Scale (VAS) at three stages: before treatment, one minute after laser irradiation, and two months later. Data were analyzed using independent t-tests, covariance analysis with repeated measures, Bonferroni’s post hoc test, and Pearson correlation coefficient test (α = 0.05). Results: The average gag reflex intensity in the intervention group was significantly lower than in the control group at all three measurement stages (p < 0.001). A significant difference was observed between the intervention and control groups immediately after treatment (p = 0.01). However, no significant difference was found between the groups two months post-treatment (p = 0.44). Gender and age did not significantly affect the reduction of gag reflex immediately after treatment or two months later. Conclusions: Photobiomodulation with diode 660 nm on acupuncture point PC-6 effectively reduced the gag reflex in these patients and made the procedure smoother and more comfortable for the patients. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024.