Individuals with Temporomandibular Dysfunction show reduced strength of the cervical muscles

Introduction: The literature indicates that individuals with temporomandibular disorder (TMD) also present pain and changes in the posture of the cervical spine, but there are still few studies that have evaluated the strength of the cervical muscles. Objectives: To evaluate cervical muscle strength in young adults with and without temporomandibular disorders. Materials and Methods: Young adults aged 18 to 25 years from a private university, with and without a diagnosis of TMD and in good general health, participated in this study. Individuals with neck/head trauma were excluded; disc herniation and degeneration; systemic diseases such as fibromyalgia, lupus; pregnancy; anesthetic block during the last 3 months. Questionnaires with general data and the Fonseca Anamnestic Index were applied to evaluate the signs and symptoms of TMD and Neck Disability Index (NDI) to assess the level of disability related to pain in the cervical spine. The assessment of muscular strength of the cervical flexor and extensor muscles measured by maximal isometric voluntary contraction (MVIC) was performed using a manual dynamometer, model 2201163, Lafayette, IN, USA. Results: A higher frequency of signs and symptoms of moderate TMD was observed (53%). A reduction in muscle strength in the TMD group was identified in relation to the group without TMD for all movements, but a significant difference was observed only in the flexion movement. Conclusion: Individuals with TMD have lower muscle strength for all movements of the cervical spine compared to individuals who do not have the same condition, and this difference is significantly present for the flexion movement.