Masticatory myofascial pain syndrome (MMPS) is a common and debilitating orofacial pain condition characterized by localized or referred pain originating from trigger points in the masticatory muscles. The condition significantly impairs quality of life, affecting mastication, speech, and psychosocial well-being. The masseter and temporalis muscles are the most frequently targeted muscles in conventional botulinum toxin type A (BoNT-A) therapy for MMPS; however, the medial pterygoid muscle, a primary jaw-closing muscle, is often overlooked due to its deep anatomical location and the technical challenges associated with its injection.
Diagnosis of myogenous TMD/myalgia according to DC/TMD.
Pain modified by jaw movement, function, or parafunction.
Familiar pain reproduced during standardized masseter/temporalis examination.
Clinical evidence of medial pterygoid involvement.
Predominantly arthrogenous TMD.
Trigeminal neuralgia or other neuropathic facial pain.
Active systemic inflammatory or infectious disease affecting the masticatory muscles.
Significant neuromuscular disease.