The objective of the study is to evaluate the effectiveness of extracorporeal shock wave therapy (ESWT) in improving pain in patients with TMD pain after 5 weeks of treatment, 1 month and 3 months after the end of treatment. As secondary objectives, we plan to evaluate the effectiveness of focal shockwave therapy in relation to:

1. Range of motion (ROM) of the temporomandibular joint using goniometry after 5 weeks of treatment;
2. Degree of inflammation, using ultrasound evaluation in the temporomandibular joint relating to the degree of pain after focal shockwave therapy for 5 weeks;
3. Jaw movement (MM), joint noise (RA), joint pressure (PA) and disability index (DI) will be measured at each treatment session and after 5 weeks of treatment, 1 month and 3 months after the end of treatment in the affected joints;
4. Quality of life will be assessed using the "Short Form Health 36" questionnaire (SF-36) during the 5 weeks of treatment, 1 month and 3 months after the end of treatment;
5. Pain control medication will also be considered and compared before and after the proposed treatment for 5 weeks.

Safety will be assessed throughout the study by monitoring the incidence of study-related adverse events. All patients will be contacted periodically and encouraged to report any side effects.

Introduction: Temporomandibular disorders (TMDs) are clinical conditions that affect the masticatory muscles, the temporomandibular joint (TMJ) and associated structures. Focal extracorporeal shock wave therapy (ESWT) can be used for the treatment of musculoskeletal disorders with good results in the literature and with the potential to treat muscular TMDs.

Objective: The aim of the study is to perform a double-blind randomized controlled clinical trial to evaluate the effects of focal shock wave therapy in the treatment of pain due to temporomandibular disorders of muscular origin in adults after 5 weeks of treatment, 1 and 3 months after the end of treatment.

Methods: A double-blind randomized controlled clinical trial will be carried out with 50 patients in the control group and 50 patients in the intervention group. Patients will be prospectively selected at the Orofacial Pain Outpatient Clinic of the Division of Dentistry, Instituto Central, Hospital das Clínicas, Faculty of Medicine, University of São Paulo (IC-HCFMUSP) and will be referred to the Acupuncture Center of the Institute of Orthopedics and Traumatology of HCFMUSP (IOT-HCFMUSP). The control group will initially undergo treatment with guidelines for muscular temporomandibular disorders and treatment by shockwave therapy with a "placebo" applicator for 5 weeks, while the intervention group will undergo the same guidelines and treatment by shockwave therapy. focal point on the masticatory muscles during 5 sessions, once a week (totaling 5 weeks). After the initial treatment period, the groups will be evaluated and compared in terms of improvement in pain and quality of life, in addition to follow-up after 1 month, 3 months and 6 months after the procedure.

Expected results: After the standardized treatment period of 1 weekly session in 5 consecutive weeks (totalizing 5 sessions), it is expected that there will be an improvement in the pain Visual Analogue Scale (VAS) and in the quality of life of patients with muscular TMDs. As there is a stimulus for differentiation of mesenchymal stem cells, neovascularization and release of angiogenic factors to occur, the effect of ESWT is expected to be lasting throughout the reassessments at 1 and 3 months.

Keywords: Temporomandibular Joint Disorders, Extracorporeal Shockwave Therapy, Temporomandibular Joint Dysfunction Syndrome, High-Energy Shock Waves, Pain Management

Inclusion Criteria:

• Pain in the temporomandibular region;
• Myofascial pain diagnosed with or without limitation of mouth opening based on the Diagnostic Criteria for TMD (DC/TMD);
• Myofascial pain associated or not with joint abnormalities;
• Presence of moderate to severe pain: Visual Analogue Scale (VAS) >4;
• Duration of TMD pain (temporomandibular musculoskeletal) ≥3 months;
• Written granting of the informed consent form to participate in the study

Exclusion Criteria:

• Abnormality in blood clotting (coagulopathy) or using some type of anticoagulant;
• Primary malignant disease (tumors) in the treatment area;
• Acute infection of soft tissue or bone;
• Systemic infections;
• Epilepsy;
• Infiltration of corticosteroids at the application site in the last 6 weeks;
• Patient at high risk of some type of anesthesia or analgesia when it eventually has to be used;
• Polyarthritis;
• Polytrauma Local joint infections;
• Previous temporomandibular surgical treatments that compromise mastication;
• Treatment by physiotherapy, acupuncture before 3 months of performing the procedures
• Depression or other mental disorders;
• Clinical diagnosis of associated fibromyalgia;
• Associated systemic inflammatory rheumatic diseases;
• Widespread pain or pain elsewhere that predominates and overlaps with TMD muscle pain;
• Inability to understand the treatment protocol.

Only Study Protocol will be shared and other details of the study (Statistical analysis plan, clinical study report) at the end of recruiting phase.

One of the researchers will keep the randomization codes out of the patients' sight. Other medical researchers, separately, will apply the shockwaves and the placebo in a non-blinded manner. One researcher will assess the outcome measures, and will be blinded to the allocation of patients into groups throughout the study.