Magnusson, T. Carlsson, G.E. Recurrent headache in relation to temporomandibular joint paindysfunction.Two groups of 80 patients, one referred because of mandibular dysfunction and one seeking dental treatment, completed questionnaires concerning recurrent headaches. The function of the masticatory system of all patients was afterwards examined clinically.The investigation showed that clenching of teeth was correlated to the severity of headache. The frequency and severity of headache varied also with the severity of mandibular dysfunction. Of the variables included in the dysfunction index, only masticatory musculature painful to palpation was found to have a distinct relationship to headaches. This implies that functional treatment is indicated in patients with headaches and tenderness of the masticatory musculature. Functional examination of the masticatory system should therefore be included in investigations of recurrent headaches.