Headaches can be due to several different mechanisms and at times a combination of them. We can enumerate some of them including Neuralgia mechanisms (cervical/trigeminal/glossopharyngeal, etc), sinus disorders, ophthalmic mechanisms (glasses, eye Strain, other eye pathology), dental mechanism (tooth decay, gum disease) and  TMJ & Jaw disorders .  TMJ disorders resulting from arthritis, inflammation, trauma or Jaw muscles pathology results in irritation of the trigeminal nerve, which result in the release of chemicals from neural receptors, causing irritation of the brain and causing recurrence primary headache. TMJ disorders can often trigger more headaches (Migraines or tension type headaches) and treatment of TMJ disorders often results in reduction in frequency of the headaches.