Eficácia da ultrassonografia terapêutica associada à terapia miofuncional orofacial na disfunção temporomandibular

Abstract

Introduction: Temporomandibular dysfunction (TMD) encompasses a set of disorders affecting the temporomandibular joint, masticatory muscles, and adjacent structures, resulting in orofacial pain, joint noises, mandibular deviations, limited mouth opening, headaches, and functional impairment in mastication and speech. The etiology of TMD is multifactorial, involving neuromuscular factors, parafunctional habits, trauma, degenerative processes, and psychosocial aspects such as stress, anxiety, and depression, which can trigger or exacerbate symptoms. Treatment generally prioritizes non-invasive approaches, including pharmacotherapy, occlusal splints, physiotherapy, speech therapy, and psychotherapy, often combined with adjuvant modalities such as low-level laser therapy, electrostimulation, biofeedback, functional taping, and therapeutic ultrasound (TUS). TUS uses high-frequency sound waves to promote analgesia, reduce inflammation, and improve blood circulation. Surgical intervention is reserved for severe or refractory cases.Objective: This study aimed to evaluate the efficacy of therapeutic ultrasound associated with orofacial myofunctional therapy (OMT) in patients with chronic muscular TMD. Methods: A randomized clinical trial was conducted involving 26 women with chronic muscular TMD, aged 18 to 55 years. Participants were randomly assigned to two groups: G1 (OMT + TUS) and G2 (OMT), undergoing four weekly sessions. Data collection included four stages: screening according to the American Academy of Orofacial Pain (AAOP), application of the DC/TMD protocol, myofunctional evaluation using AMIOFE, and therapeutic intervention. OMT included thermotherapy, stretching, muscle relaxation, mandibular mobility exercises, and functional mastication training. TUS was applied to the masseter and anterior temporal muscles. Both groups received guidance on parafunctional habits and home exercises. Outcome measures included pain intensity, pressure pain threshold (PPT), mandibular range of motion, masticatory function, depressive symptoms, anxiety levels, frequency of parafunctional oral behaviors, and interference of pain in daily activities. Results: The OMT + TUS group showed significant improvement in maximal mouth opening (MMO) and mandibular protrusion, with a large effect size, and trends toward significance in right lateral movement and assisted maximal mouth opening. Both groups experienced significant pain reduction, slightly greater in the combined group. Mandibular functional limitation decreased only in the OMT group, while masticatory function improved in specific tasks only in the OMT + TUS group. Although changes in masticatory patterns were not statistically significant, the combined group demonstrated favorable clinical reorganization, showing a transition toward more functional bilateral patterns. The association between depression and parafunctional oral behavior was significant in the OMT group before intervention and disappeared afterward; in the OMT + TUS group, it became significant after intervention, with moderate depression and anxiety associated with high-level parafunctional behavior. No significant association was observed between pain intensity and other psychosocial variables. Conclusion: Although statistically significant efficacy of the OMT + TUS combination was not observed, the clinical effects suggest promising therapeutic potential, particularly regarding pain, mandibular mobility, and masticatory function. Findings in the combined group indicate that pain improvement may mask residual psychological symptoms, emphasizing the importance of integrated approaches addressing both physical and emotional aspects of TMD. Future studies with longer intervention periods are recommended to more comprehensively evaluate the effects of this therapeutic combination.