Perception of cutaneous electrical stimulation in patients with craniomandibular disorders

Perception thresholds for stimulation, discomfort, and pain were measured with electrical stimulation over the masseter area. Patients with chronic symptoms and signs of craniomandibular disorders reported significantly higher thresholds of all three variables compared with healthy controls. There were significantly negative correlations between the patients' pre-experimental discomfort and pain ratings on the Borg's scale and perception thresholds measured for discomfort and pain. The patients who presented the highest pain ratings in masticatory muscles and/or joints had the lowest threshold values when reporting discomfort and pain during gradually increased current intensity. This could be due to the cognitive effects of pain.