Temporomandibular Disorders (TMD) are a common source of pain and functional limitation affecting the stomatognathic system. They frequently lead to difficulties in mastication, decreased quality of sleep, limited mandibular mobility, and restrictions in daily activities. These symptoms are often aggravated in patients with associated bruxism. Chronic involvement of the temporomandibular joint and surrounding structures can also negatively influence cervical posture and motor control due to the neurophysiological connections between the cranio-cervical region and mandibular biomechanics. This study is designed to evaluate whether active mandibular techniques, specifically the Muscle Energy Technique (MET) applied with the support of the jaw motion rehabilitation system, combined with a cranio-cervical therapeutic exercise program, may improve pain, function, and motor behavior in patients with chronic TMD and bruxism.
The trial will be conducted as a randomized controlled study with two parallel groups. The experimental group will receive a mandibular MET intervention delivered once weekly for four weeks, using an active resistance and controlled movement protocol based on three cycles of isometric contraction and passive stretching. In addition, participants will perform daily cranio-cervical motor control exercises at home, with weekly supervision. These exercises aim to enhance neuromuscular regulation of deep cervical flexors and extensors and improve cervical dissociation, symmetry, and alignment. The control group will receive standard clinical care supplemented by a single session of a modified suboccipital inhibition technique acting as a placebo procedure. They will also perform non-specific cervical mobility exercises at home over a four-week period.
The primary outcome will be the change in Pressure Pain Threshold (PPT) measured with a pressure algometer at trigger points located in the trapezius, masseter, external pterygoid, and digastric muscles. Secondary outcomes will include maximum mouth opening, pain intensity using a visual analog or numeric rating scale, craniocervical postural control assessed through standardized motor control evaluations, and mandibular movement behavior analyzed through visual or device-assisted kinematic assessment. Measurements will be taken at baseline, immediately after the intervention period, and during a follow-up assessment.
Participants will be adults aged 18 to 65 years with a clinical diagnosis of TMD associated with pain for at least three months and bruxism. All participants must provide informed consent prior to inclusion. Individuals with congenital malformations or cervical spine pathology, acute infectious or inflammatory disease, vestibular dysfunction, technical contraindications, recent manual therapy treatment (within one month), or recent use of analgesic, muscle relaxant, or anti-inflammatory medication (within eight hours) will be excluded.
The study aims to determine whether the application of active mandibular techniques combined with specific cervical motor control training results in superior improvements in function and pain compared to standard clinical management. Furthermore, the analysis will consider sex-related differences in baseline characteristics and treatment outcomes. Results from this trial may provide clinically relevant evidence to guide physiotherapeutic approaches for patients with TMD and bruxism, potentially improving therapeutic decision-making and long-term patient outcomes. The findings will be disseminated through publication in high-impact international journals and presentation at scientific conferences.