Headache and temporomandibular disorders: evidence for diagnostic and behavioural overlap.

To assess the diagnostic and behavioural overlap of headache patients with temporomandibular disorders (TMD), individuals recruited from the general population with self-described headaches were compared with non-headache controls. The examination and diagnostic procedures in the Research Diagnostic Criteria (RDC) for TMD were applied to both sets of subjects by a blinded examiner. Following their examination, subjects used experience sampling methods to obtain data on pain, tooth contact, masticatory muscle tension, emotional states and stress. Results showed that a significantly higher proportion of the headache patients received an RDC/TMD diagnosis of myofascial pain than non-headache controls. Headache patients also reported significantly more frequent and intense tooth contact, more masticatory muscle tension, more stress and more pain in the face/head and other parts of the body than non-headache controls. These results are similar to those reported for TMD patients and they suggest that headache patients and TMD patients overlap considerably in diagnosis and oral parafunctional behaviours.