mastication muscles

Question 1

masseter

Answer 1

• origin: zygomatic arch and zygomatic bone
• insertion: lateral surface of the ramus and angle of the mandible
• action: elevates the mandible

Question 2

temporalis

Answer 2

• origin:temporal fossa and the temporal fascia
• insertion: coronoid process of the mandible and the anterior surface of the ramus of the mandible
• action: elevates the mandible; retracts the mandible (posterior fibers)

Question 3

lateral pterygoid

Answer 3

• origin: superior head: greater wing of the sphenoid bone; inferior head: lateral pterygoid plate
• insertion: superior head: capsule and & articular disk of the temporomandibular joint; inferior head: neck of the mandible
• action: protracts and elevates mandible

Question 4

medial pterygoid

Answer 4

• origin: medial surface of the lateral pterygoid plate, pyramidal process of the palatine bone, tuberosity of the maxilla
• insertion: medial surface of the ramus and angle of the mandible
• action: elevates and protracts the mandible