Effectiveness of Transcutaneous Auricular Vagus Nerve Stimulation in Bruxism: A Randomised, Controlled, Single-Blind Experimental Trial

Abstract

Background: Transcutaneous auricular vagus nerve stimulation (TAVNS) stands out as a neuromodulation method that shows therapeutic potential thanks to its ability to regulate autonomic responses. However, the role of TAVNS in the management of bruxism-related clinical parameters has not been sufficiently investigated. Objective: This study aimed to investigate the holistic effects of TAVNS added to exercise therapy on bruxism-related clinical parameters in patients with clinically based bruxism. Methods: This randomised, controlled, single-blind experimental clinical study included 40 individuals diagnosed with clinically based bruxism, who were randomly assigned to two groups: the TAVNS group (n = 20) and the control group (n = 20). Both groups performed the Rocabado exercise program for 8 weeks, while the TAVNS group additionally performed TAVNS. Oral health-related quality of life, sleep quality, perceived stress level, pain intensity, pain threshold, biomechanical properties of masticatory muscles, masseter muscle activation and autonomic parameters were evaluated before and after treatment. Results: The TAVNS group showed significantly better results in oral health-related quality of life, stress levels, masseter muscle functional parameters (resting activation, tonus, stiffness), and autonomic parameters (pulse rate, respiratory rate, sympathetic activity, sympathovagal balance) compared to the control group (p < 0.05). Conclusion: This study revealed that TAVNS added to exercise therapy provided significant improvements in key clinical parameters associated with bruxism, including both local symptoms (muscle activation and biomechanical properties) and systemic parameters (autonomic parameters, stress, oral health-related quality of life) in bruxism. Although our findings support the clinical potential of TAVNS as a non-invasive complementary option for managing bruxism-related dysfunctions, these effects need to be confirmed in larger samples and long-term follow-ups. Trial Registration: ClinicalTrials.gov identifier: NCT06386809.