Muscles That Move the Mandible and Assist in Mastication and Speech

Question 1

Masseter

Answer 1

Origin – zygomatic arch

Insertion-angle and ramus of mandible

Action- Elevate the mandible [Temporomandibular joint]
May assist to protract the mandible [TM joint]

Innervation-trigeminal [ V] nerve [mandibular division]

Question 2

Temporalis

Answer 2

O- temporal fossa & fascia

I- coronoid process and anterior edge of ramus of the mandible

A- Elevate the mandible [temporomandibular joint]
Retract the manual [TM joint]

N- trigeminal [ V] nerve [mandibular division]

Question 3

Medial pterygoid

Answer 3

O-Medial surface of lateral pterygoid plate of sphenoid bone and tuberosity of maxilla

I-Medial surface ramus of the mandible

A-Unilaterally: laterally deviate the mandible to the opposite side
Bilaterally: elevate available, protract the mandible

N-Trigeminal [V]

Question 4

Lateral pterygoid

Answer 4

O-Superior head: Infratemporal surface and crest of greater wing of sphenoid bone
Inferior head: lateral surface of lateral pterygoid plate of sphenoid bone

I-Articular disc and capsule of temporomandibular joint, neck of mandible

A-Unilaterally: laterally deviate the mandible to the opposite side

N-Trigeminal [ V]