Immediate Effects of Dry Needling in Patients with Myofascial Temporomandibular Disorders: A Randomized Controlled Trial

Background: Myofascial temporomandibular disorders (TMDs) are associated with pain and trigger points in the masticatory muscles. Dry needling (DN) is used for myofascial pain, but evidence regarding immediate effects remains limited. Objective: This participant- and outcome-assessor-blinded randomized controlled trial evaluated immediate clinical and electromyographic effects of a single DN session targeting the masseter and anterior temporalis muscles in patients with myofascial TMD. Methods: Forty-four participants diagnosed according to the Research Diagnostic Criteria for Temporomandibular Disorders were randomly allocated to a DN group or a sham needling group. Pain intensity was assessed using a visual analog scale, and surface electromyographic activity of the masseter and anterior temporalis muscles was recorded at rest and during maximal clenching. Measurements were obtained before treatment and 10 min after the intervention. Adverse events were recorded throughout the observation period. Results: Forty participants completed the study, with 20 in each group. Pain intensity decreased significantly in the DN group compared with the sham group (p < 0.001). An uncorrected analysis indicated reduced resting activity of the left anterior temporalis muscle; however, no electromyographic variable remained significant after correction for multiple comparisons. No serious adverse events occurred. Minor transient bleeding and mild post-needling soreness were reported in a small number of participants receiving DN. Conclusions: A single DN session produced a significant immediate reduction in pain intensity in patients with myofascial TMD, without consistent immediate changes in surface electromyographic activity. Longer follow-up and repeated-session studies are needed to determine the durability and clinical relevance of these effects.