[TA] masticatory muscle of infratemporal fossa; origin, inferior head from lateral lamina of pterygoid process; superior head from infratemporal crest and adjacent greater wing of the sphenoid; insertion, into pterygoid fovea of mandible and articular disc and capsule of temporomandibular joint; action, protrudes lower jaw to enable opening of mouth; unilateral contraction deviates chin laterally, enabling grinding motion for chewing; nerve supply, nerve to lateral pterygoid from mandibular division of trigeminal. SYN: musculus pterygoideus lateralis [TA], external pterygoid muscle, musculus pterygoideus externus.
