Mastication Muscles

Question 1

Temporalis

Answer 1

Origin: Temporal Fossa & Temporal Fascia
Insertion: Mandible
Function: Elevates & retracts the mandible
Innervation: Mandibular nerve

Question 2

Masseter

Answer 2

Origin: Maxillar & Zygomatic Bones
Insertion: Mandible
Function: Elevates the mandible
Innervation: Mandibular Nerve

Question 3

Digastric

Answer 3

Origin: (anterior) Mandible & (posterior) Temporal bone
Insertion: both heads meets into the the Intermediate tendon
Function: Depression & stabilization of the hyoid bone
Innervation: CN 7

Question 4

Lateral Pterygoid

Answer 4

Origin: Both heads originates from the sphenoid bone
Insertion: Lower head inserts in the mandible & upper head inserts capsule of the TMJ
Function: Protraction of the TMJ & Deviation of the mandible (lower head only)
Innervation: Mandibular Nerve

Question 5

Medial Pterygoid

Answer 5

Origin: Sphenoid bone & Maxilla & Palatine Bone
Insertion: Mandible
Function: Elevates the mandible and also contributes to lateral and protrusive movements
Innervation: Mandibular Nerve

Question 6

Mylohyoid

Answer 6

Origin: Mandible
Insertion: Mandible & Hyoid Bone
Function: Depress the mandible when the hyoid is fixed
Innervation: Mandibular Nerve