The worse the TMD, the more severe and frequent the migraine attacks, researchers have discovered.
Chronic migraine sufferers, which is defined as having 15 days or more a month of attacks, are also three times more likely to have severe TMD, researchers from the University of Sao Paulo discovered.
They monitored 84 young women, made up of 21 chronic sufferers, 32 with episodic migraine, and 32 healthy controls. Every single one of the chronic sufferers also had the severest TMD, and 80 per cent of those with episodic migraine had some TMD, as did half of the participants who didn't have migraine.
Although there's a link, the researchers aren't convinced that TMD causes migraine, or vice versa. Instead, it's more a vicious circle where migraine makes the sufferer more sensitive to pain, and this predisposes people to TMD, and this, in turn, helps perpetuate migraine.
TMD, which affects the joints that act like a sliding hinge that connects the jawbone to the skull, is stress-related and has to do with muscle overload, the researchers say. Its symptoms include joint pain, reduced jaw movement, difficulty chewing, clicking or popping of the jaw, and muscle pain and fatigue that can radiate to the face and neck.
Although most migraine sufferers seem to also have TMD, people with TMD don't necessarily develop migraine, the researchers point out.