Muscles of Mastication Flashcards
What are the muscles of mastication associated with?
movements of the jaw (temporomandibular joint).
What are the muscles of mastication?
- Masseter
- Temporalis
- Medial pterygoid
- Lateral pterygoid
What are the muscles of mastication innervated by?
CN V3 (motor component)
What is the most powerful muscle of mastication?
Masseter
Attachments of masseter?
The entirety of the muscle lies superficially to the pterygoids and temporalis, covering them.
Originate: zygomatic process of temporal bone
Inserts: ramus of mandible (near the angle)
What is the action of masseter?
Elevates the mandible, closing the mouth
Attachments of temporalis?
Origin: temporalis fossa
Inserts: coronoid process of mandible
Action of temporalis?
- Elevates the mandible, closing the mouth
- Retracts the mandible, pulling the jaw posteriorly
Attachments of medial pterygoid? (note this muscle has 2 heads)
Origin:
- Superficial head: the maxillary tuberosity and the pyramidal process of palatine bone.
- Deep head: medial surface of lateral pterygoid plate of the sphenoid bone
Inserts: Ramus of the mandible (near the angle)
Attachments of lateral pterygoid? (note this muscle has 2 heads)
Origin:
- The superior head: originates from the greater wing of the sphenoid.
The inferior head: originates from the lateral pterygoid plate of the sphenoid
Inserts: neck of mandible
Action of the medial pterygoid?
Elevates the mandible, closing the mouth.
Action of the lateral pterygoid?
Acting bilaterally, the lateral pterygoids protract the mandible, pushing the jaw forwards. Unilateral action produces the ‘side to side’ movement of the jaw.
