Radiographic evaluation of cervical spine of subjects with temporomandibular joint internal disorder.

Although the etiopathophysiology of internal temporomandibular joint internal disorders (TMJ ID) is still unknown, it has been suggested that head and body posture could be related to its initial onset, development and perpetuation. The purpose of the present study was to observe the relationship between cervical spine X-ray abnormalities and TMJ ID. This investigation evaluated 30 subjects with internal TMJ disorder symptoms (test group) and 20 healthy subjects (control group). Subjects were submitted to clinical and radiographic evaluation. Clinical evaluation comprised anamnesis and stomatognathic system physical examination. Radiographic evaluation comprised analysis of lateral cervical spine X-rays by three physical therapists and tracing on the same images. The test group presented twice as much cervical spine hyperlordosis as the control group (20.7% versus 10.5%), but almost half of rectification prevalence (41.4 versus 79.0%, p = 0.03). After that, the test group was divided into three subgroups according to TMJ dysfunction severity, evaluated by Helkimo's index. These subgroups were not significantly different, but the subgroup with more severe TMD showed a tendency to cervical spine hyperlordosis prevalence. Results showed a tendency for subjects with more severe TMD to exhibit cervical spine hyperlordosis. Nevertheless, studies with a larger number of subjects suffering from severe TMD are encouraged in order to corroborate the present findings.