Trigger point dry needling increases masseter muscle oxygenation in patients with temporomandibular disorder

• Published in: Journal of applied oral science Vol. 31; p. e20230099
• Main Authors: Macedo, Carolina Ferreira de, Sonza, Anelise, Puel, Alexia Nadine, Santos, Adair Roberto Dos
• Format: Journal Article
• Language: English
• Published: Brazil Faculdade De Odontologia De Bauru - USP 01-01-2023; University of São Paulo
• Subjects: Craniomandibular disorder; DENTISTRY, ORAL SURGERY & MEDICINE; Dry Needling; Female; Humans; Male; Masseter Muscle; Muscle oxygenation; NIRS; Original; Pain; Temporomandibular Joint Disorders - therapy; Trigger Points; NIRS; Craniomandibular disorder; Muscle oxygenation; Masseter muscle; Dry needling
• ISSN: 1678-7757; 1678-7765; 1678-7765
• DOI: 10.1590/1678-7757-2023-0099

Temporomandibular disorder (TMD) is an umbrella term encompassing various clinical complaints involving the temporomandibular joints, masticatory muscles, and/or associated orofacial structures. Myogenous TMDs are the most frequent cause of chronic orofacial pain. Musculoskeletal pain is commonly associated with myofascial trigger points (MTPs), for which dry needling (DN) is a routine treatment.
To investigate muscle oxygenation and pain immediately after DN application on an MTP in the masseter muscle of patients with myogenous TMDs.
Masseter muscle oxygen tissue saturation indices (TSI%) were assessed by near-infrared spectroscopy (NIRS) pre- and post-interventions by a randomized, controlled, double-blind, crossover DN/Sham clinical trial (primary outcome). Pain was investigated by the visual analog scale (VAS). In total, 32 individuals aged from 18 to 37 years who were diagnosed with myogenous TMD and myofascial trigger points in their masseter muscles participated in this study. Relative deltas for the studied variables were calculated. Data normality was tested using the Shapiro-Wilk test. According to their distribution, data were analyzed by two-way ANOVA and the Student's t-, and Mann-Whitney tests. Statistical analyses were performed using Prism® 5.0 (GraphPad, USA).
We found a significant difference (2,108% vs. 0,142%) between masseter muscle TSI% deltas after the DN and Sham interventions, respectively (n=24). We only evaluated women since men refused to follow NIRS procedures. Pain increased immediately after DN (n=32, 8 men), in comparison to Sham delta VAS.
These findings show an increase in tissue oxygen saturation in the evaluated sample immediately after the DN intervention on the MTP of patients' masseter muscle. Pain may have increased immediately after DN due to the needling procedure.