Abstract:Objective:To investigate the value of the trigeminal exteroceptive suppression(ES) of temporalis and masseter muscles to examine tnsion-type headache (TTH) sufferers. Methods:The ES was examined in 30 patients with TTH and 30 normal volunteers by electritic stimulation on infraobital region utilizing electromyography(EMG),to measure the latency and duration of ES in temporalis and masseter muscles. Results:The onset latency of the second exteroceptive suppression period (ES2) was prolonged and the duration of ES2 was shorter in patients with TTH than those obtained from controls,as well as,the frequency of ES2 was lower(P<0.05). Conclusion:The ES may be useful to diagnose and research in TTH.