Muscles of the Face

Question 1

Orbicularis oculi

Answer 1

ORIGIN:
orbital part - medial part of orbital margin
palpebral part - medial palpebral ligament
lacrimal part - lacrimal bone
INSERTION: skin surrounding orbit, lateral palpebral ralphe, upper and lower eyelids
ACTION: closure of eyelids
INNERVATION: CNVII (facial nerve)

Question 2

Orbicularis oris

Answer 2

ORIGIN: medial maxilla and mandible, deep surface of peri-oral skin, angle of mouth
INSERTION: skin and fascia of the lips
ACTION: compression and protrusion of lips
INNERVATION: CNVII (facial nerve)

Question 3

Buccinator

Answer 3

ORIGIN: buccinator ridge of mandible, alveolar process of maxilla, pterygomandibular raphe
INSERTION: angle of the mouth and lateral portion of upper and lower lips
ACTION: builds muscular substructure of cheeks, controls food synergistically with tongue, draws mouth unilaterally
INNERVATION: CNVII (facial nerve)

Question 4

Nasalis

Answer 4

ORIGIN: lateral to nasal notch of maxilla
INSERTION: midline aponeurosis at the bridge of the nose
ACTION: opens and closes nostrils
INNERVATION: CNVII (facial nerve)

Question 5

Temporalis

Answer 5

ORIGIN: temporal fossa, temporal fascia
INSERTION: ramus and coronoid process of mandible
ACTION:
unilateral - lateral deviation of mandible (ipsilateral)
bilateral - elevation and retraction of mandible
INNERVATION: CNV (trigeminal nerve)

Question 6

Masseter

Answer 6

ORIGIN: zygomatic arch
INSERTION: angle and lateral surface of ramus of mandible
ACTION:
unilateral - lateral deviation of mandible (ipsilateral)
bilateral - elevation and protrusion of mandible
INNERVATION: CNV (trigeminal nerve)

Question 7

Lateral pterygoid

Answer 7

ORIGIN:
superior head - infratemporal surface of greater wing of sphenoid
inferior head - lateral surface of lateral pterygoid plate
INSERTION: condyle of mandible, capsule and articular disc of temporomandibular joint
ACTION:
unilateral - lateral deviation of mandible (contralateral)
bilateral - protrusion and depression of mandible
INNERVATION: CNV (trigeminal nerve)

Question 8

Medial pterygoid

Answer 8

ORIGIN:
deep head - medial surface of lateral pterygoid plate of sphenoid bone and adjacent pyramidal process of palatine bone
superficial head - tuberosity of maxilla
INSERTION: medial surface of angle and ramus of mandible
ACTION:
unilateral - lateral deviation of mandible (contralateral)
bilateral - protrusion and elevation of mandible
INNERVATION: CNV (trigeminal nerve)