Aims: To investigate how often healthy controls and patients with myogenous masticatory pain have wake-time nonfunctional tooth contact, whether the frequency of nonfunctional tooth contact differs between genders or between weekdays and weekends, and whether it is influenced by stress levels. Methods: The study was performed on 24 subjects: 15 controls and 9 patients with myogenous facial pain. Before data collection the subjects were trained to ascertain their ability to feel correctly whether their teeth were in contact or apart. Subsequently, for 10 days the subjects were alerted by means of a radio wave-activated wrist vibrator approximately every 20 minutes (8:00 am to 10:00 pm) in order to report whether the teeth were in contact. Subjects also completed 2 stress assessment questionnaires, the Perceived Stress Scale (PSS) and the short version of the Trier Inventory for Assessment of Chronic Stress (TICS-S). Results: There was a significantly higher frequency of wake-time nonfunctional tooth contact in myogenous pain patients than in controls (median of 34.9% and range of 26.5% to 41.3% for patients; median of 8.9% and range of 2.3% to 14.3% for controls; P .001). In both groups the frequency of nonfunctional tooth contact did not significantly differ among the various days or between the genders. The patients had significantly higher PSS scores and reported having experienced more stressful situations in the dimensions "social overload" and "overextended at work" than the controls. However, PSS and TICS-S scores were not correlated with the frequency of nonfunctional tooth contact for either group. Conclusions: Myogenous pain patients had nearly 4 times more nonfunctional tooth contact during wake time than controls. Palabras clave: bruxism, ecological momentary assessment, tooth clenching, tooth contact