Standardized palpation of the temporalis muscle evoke referred pain and sensations in individuals without TMD.

This study aimed to determine if standardized palpations of the temporalis muscle evoke referred pain and/or sensations in individuals without TMD. This was a randomized, single-blinded study. The mechanical sensitivity of the right temporalis muscle was assessed in 32 participants without TMD with nine different stimulations to 15 test sites using palpometers (different stimulus intensities (0.5, 1.0, and 2.0 kg) and durations (2, 5, and 10 s). After each stimulus, participants were asked to score perceived pain intensity and intensity of unpleasantness on a 0–100 numeric rating scale as an indicator of mechanical sensitivity in the temporalis muscle and to indicate any areas of referred pain/sensations on a body chart. Pain intensity significantly differed between palpation durations, intensities, and test sites (P < 0.001). In contrast, unpleasantness significantly differed between palparation duration and intensities (P < 0.001), but not test sites. Participants more frequently reported referred pain/sensations evoked by the 10-s (34.4%) as opposed to the 2-s (6.3%) and 5-s (15.6%) palpation duration at the 2.0-kg stimulus intensity (P < 0.05). Our present results indicate that referred pain/sensations in the orofacial region can be evoked by standardized palpation of the temporalis muscle and influenced by the palpation duration in individuals without TMD. Referred pain/sensations from the temporalis muscle were duration- and intensity-dependent processes originating from local stimuli.