[Migraine and temporomandibular joint dysfunction: mechanisms of comorbidity].

OBJECTIVE: to analyze the frequency of different forms of temporomandibular joint dysfunction (TMJD) in episodic and chronic migraine and to study mechanisms of their comorbidity. MATERIAL AND METHODS: Sixty-three patients with chronic migraine (CM) and 40 patients with episodic migraine (EM) were examined. Anxiety and depression were assessed with the HADS, quality-of-life related to headache was measured with the HIT-6. To evaluate the antinociceptive system function, we studied blink reflex (BR) and nociceptive flexion reflex (NFR). RESULTS: The higher frequency of TMJD was identified in patients with CM compared to those with EM (47.5 and 28.5%, respectively), CM patients more frequently had disturbances related to the myofascial pain syndrome of masticatory muscles. R3 BR and NFR thresholds were significantly decreased in CM patients as well. CONCLUSION: TMJD is a component of the pathogenesis in many patients with CM. Masticatory muscles may generate nociceptive impulses in CNS, ie be a source of peripheral sensitization, that promote pain chronification, including migraine. Dysfunction of masticatory muscles may reflect the central sensitization and disturbance of efferent pain control.