- Male reproductive system
- Lymphatic system
- Skeletal system
- Blood vessels
- Respiratory system
- Digestive system
- Endocrine glands
- Nervous system
- Female reproductive system
The medial pterygoid (Latin: musculus pterygoideus medialis) is a thick and quadrilateral-shaped muscle located in the infratemporal fossa of the skull. It is classified as one of the primary muscles of mastication. The medial pterygoid is composed of two heads - superficial (smaller) and deep (larger). This muscle provides movements of the mandible at the temporomandibular joint (TMJ).
Superficial head - maxillary tuberosity of maxilla, pyramidal process of palatine bone
Deep head - medial surface of lateral pterygoid plate (sphenoid bone)
|Insertion||Pterygoid tuberosity of mandible, medial surface of mandibular ramus|
Bilateral contractions - push mandible forward, elevate mandible
Unilateral contraction - pushes mandible to opposite side
|Innervation||Medial pterygoid nerve of mandibular nerve|
|Blood supply||Pterygoid branches of maxillary, buccal and facial arteries|
The superficial head of the medial pterygoid muscle originates from the maxillary tuberosity of the maxilla and pyramidal process of the palatine bone. The deep head of the muscle originates from the medial surface of the lateral pterygoid plate (of the sphenoid bone).
The medial pterygoid inserts on the pterygoid tuberosity of the mandible and medial (inner) surface of the mandibular ramus.
Upon bilateral contractions, the medial pterygoid muscles push the mandible forward (protrude the mandible). By contracting on one side, the medial pterygoid pushes the mandible to the opposite side. This muscle also contributes to the elevation of the mandible, acting as a synergist to the temporalis and masseter.