Muscle
Lateral pterygoid
Protrudes the jaw, opens the mouth
High-yield
Only muscle of mastication that OPENS the jaw (protraction/depression). "Lateral = Lowers." CN V3.
Overview
A two-headed muscle that protrudes the mandible and depresses it to open the mouth; the only muscle of mastication that opens the jaw.
Reference facts
- Origin
- Greater wing of the sphenoid (upper head) and lateral pterygoid plate (lower head)
- Insertion
- Neck of the mandible, articular disc, and capsule of the TMJ
- Action
- Protrudes and depresses the mandible (opens the mouth); side-to-side grinding when unilateral
- Innervation
- Nerve to lateral pterygoid from the mandibular division (CN V3)
- Blood supply
- Pterygoid branches of the maxillary artery
Frequently asked questions
What does the lateral pterygoid do?
The lateral pterygoid protrudes and depresses the mandible (opens the mouth); side-to-side grinding when unilateral.
What nerve innervates the lateral pterygoid?
The lateral pterygoid is innervated by the nerve to lateral pterygoid from the mandibular division (CN V3).
Where does the lateral pterygoid attach?
The lateral pterygoid originates from the greater wing of the sphenoid (upper head) and lateral pterygoid plate (lower head) and inserts on the neck of the mandible, articular disc, and capsule of the TMJ.
What is the blood supply of the lateral pterygoid?
The lateral pterygoid is supplied by the pterygoid branches of the maxillary artery.