Muscles of mastication

Question 1

Masseter

Answer 1

Attachments: from the zygomatic arch to the angle of the mandible & lateral aspect of the ramus

Function: elevation, protraction & retraction (deep fibers) of the mandible

Innervation: mandibular n.

Blood supply: masseteric, facial & transverse facial a.

Question 2

Temporalis

Answer 2

Attachments: from the temporal fossa to the coronoid process & anterior border (temporal crest) of the ramus of the mandible

Function: elevation & retraction (posterior aspect of the muscle) of the mandible

Innervation: mandibular n.

Blood supply: deep temporal a.

Question 3

Lateral pterygoid

Answer 3

Attachments: from the infratemporal surface of the sphenoid & lateral surface of the lateral pterygoid plate to the pterygoid fovea of the mandible & the TMJ disc

Function: protraction of the mandible & acts with the ipsilateral medial pterygoid to rotate the mandible to produce side-to-side movements during trituration of food

Innervation: mandibular n.

Blood supply: pterygoid & ascending palatine a.

Question 4

Medial pterygoid

Answer 4

Attachments: from the medial surface of the lateral pterygoid plate & adjacent pterygoid fossa to the medial aspect of the angle of the mandible

Function: elevation of the mandible & acts with the ipsilateral lateral pterygoid to rotate the mandible to produce side-to-side movements during trituration of food

Innervation: mandibular n.

Blood supply: pterygoid a.