Temporomandibular disorders (TMD) are common musculoskeletal conditions frequently accompanied by cervical dysfunction. Although previous studies have demonstrated associations between cervical impairments and temporomandibular symptoms, the influence of chronic neck pain on cervical function and its contribution to temporomandibular outcomes remain incompletely understood.

This cross-sectional study aims to compare cervical and temporomandibular characteristics between individuals with TMD with chronic neck pain and those without chronic neck pain, and to identify cervical factors associated with temporomandibular function, maximal mouth opening, and temporomandibular pain. A total of 67 adults diagnosed with TMD according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) will be enrolled and allocated into two groups based on the presence or absence of chronic neck pain.

Participants will undergo comprehensive assessments including temporomandibular joint range of motion, maximal mouth opening, Jaw Functional Limitation Scale-20 (JFLS-20), craniovertebral angle, cervical range of motion, deep cervical flexor muscle endurance, cervical proprioception, Neck Disability Index (NDI), and pain intensity using the Visual Analog Scale (VAS). Group differences and the relationships between cervical function and temporomandibular outcomes will be examined using correlation and regression analyses.

The findings are expected to clarify the contribution of cervical posture, mobility, muscle endurance, and proprioception to temporomandibular dysfunction. The results may support the incorporation of comprehensive cervical assessment and cervical-focused rehabilitation strategies into the clinical management of individuals with temporomandibular disorders.