Head and neck muscles (chewing, facial, and throat muscles)

Medial pterygoid

Musculus pterygoideus medialis

Origin

Inner surface of the lateral pterygoid plate (sphenoid bone) and the maxillary tuberosity

Insertion

Inner surface of the ramus and angle of the mandible

Function

Elevation (closing) of the mandible; together with lateral pterygoid, assists the grinding motion during chewing

Innervation

Medial pterygoid nerve (branch of CN V3)

Movement & chain

Forms a muscular sling with masseter around the angle of the mandible; works synergistically in jaw closing and, together with the contralateral lateral pterygoid, in lateral chewing movements.

Palpation

Palpable intraorally medial to the ramus of the mandible; difficult to distinguish externally from surrounding structures.

Clinical

Can become tense with bruxism, contributing to jaw clenching (trismus) and pain on mouth opening.

Segmental innervation

Mandibular nerve (V3), motor.

In clinical practice

Powerful jaw elevator; intraoral trigger point release and occlusal splint therapy for severe bruxism and masticatory myalgia.

Region in the model

Head and neck muscles (chewing, facial, and throat muscles)