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- For Pain Patients and Professionals
Abnormal endogenous pain modulation (EPM) was suggested as a pathophysiological characteristic of chronic pain. EPM has been investigated using psychophysical tests for pain facilitation and inhibition such as temporal summation of pain and conditioned pain modulation, respectively. Another psychophysical test for pain inhibition is offset analgesia (OA), where small variations in noxious stimulus intensity over time elicit a disproportionately large analgesic response. OA has been investigated in patients with mixed pain conditions, but not in chronic temporomandibular disorders (TMD) patients.