Facial Nerve and Muscles of Facial Expression

Question 1

the facial nerve enters through the

Answer 1

petrous part of the temporal bone through the internal auditory meatus

Question 2

after passing through the internal auditory meatus, the facial nerve then passes through

Answer 2

the petrous temporal bone within the facial canal

Question 3

the facial nerve exits the skull through

Answer 3

the stylomastoid foramen, behind the ear

Question 4

after the facial nerve exits the skull the nerve then enters the

Answer 4

parotid gland on the face

Question 5

within the parotid gland the facial nerve divides into

Answer 5

5 motor branches that innervate muscles of facial expression

Question 6

branches of the facial nerve

Answer 6

temporal
zygomatic
buccal
marginal mandibular
cervical

Question 7

motor fibres in the facial nerve supply

Answer 7

muscles of facial expression
several other muscles: digastric muscle, stylohyoid and stapedius muscle

Question 8

general sensory fibres in the facial nerve supply

Answer 8

skin of the external ear (posterior auricular nerve)

Question 9

special sensory of taste fibres in the facial nerve carry

Answer 9

taste sensation from the anterior 2/3 of the tongue via chorda tympani branch

Question 10

parasympathetic fibres in the facial nerve supply

Answer 10

lacrimal gland (produces tears)
submandibular and sublingual salivary glands

Question 11

frontalis muscles

Answer 11

originates from the membrane (aponeurosis) in the scalp
inserts into the skin at eyebrows and root of the nose
expression - surprise

Question 12

orbicularis oculi

Answer 12

circular muscle around the eye
orbital part (circular, larger part): tightly closes eyelids, protects the eye
palpebral part (in eyelids, smaller): runs horizontally in upper and lower eyelids; gently closes eyelids, blinking

Question 13

orbicularis oris

Answer 13

circular muscle around the mouth
closes/compresses the lips
most muscles in the mouth region insert into orbicularis oris

Question 14

buccinator muscle

Answer 14

runs horizontally, inserts into the corner of the mouth
compresses the cheeks and lips against the teeth
helps during mastication by preventing food from collecting between the cheek and teeth
contracts when whistling or playing wind instruments

Question 15

muscles of the upper lip

Answer 15

zygomaticus major: smiling muscle, inserts at the corner of the mouth

levator anguli oris: inserts at the corner of the mouth, elevates corner of the mouth

levator labii superioris: inserts at the upper lip, elevates upper lip

Question 16

muscles of the lower lip

Answer 16

depressor anguli oris: triangular; inserts into corner of the mouth; depresses corner of the mouth

depressor labii inferioris: inserts into the lower lip; depresses lower lip

Question 17

mentalis muscle

Answer 17

short, thick muscle at the tip of the chin
raises the skin of chin

Question 18

platysma muscle

Answer 18

very thin muscular sheet in the neck
originates in the skin over clavicle
inserts to the lower border of the mandible
shaving muscle

Question 19

occipitalis muscle

Answer 19

muscle of facial expression on the back of the head
attaches to the occipital bone
inserts into the aponeurosis in the scalp

Question 20

masseter muscle

Answer 20

not a muscle of facial expression
it is a muscle of mastication

Question 21

temporal branch innervation

Answer 21

frontalis

Question 22

zygomatic branch innervation

Answer 22

orbicularis oculi

Question 23

buccal branch innervation

Answer 23

buccinator, zygomaticus major, levator labii superiors, levator anguli oris

Question 24

marginal mandibular innervation

Answer 24

depressors labii inferiors, depressor anguli oris, mentalis

Question 25

cervical innervation

Answer 25

platysma

Question 26

posterior auricular innervation

Answer 26

occipitalis

Question 27

bell’s palsy

Answer 27

sudden facial paralysis; unilateral
damage to the facial nerve
etiology unknown
research: herpes simplex virus, herpes zoster
severe case: ipsilateral eye cannot be closed, salivation and lacrimation affected
most patients recover spontaneously
no specific treatment

Question 28

parotid gland

Answer 28

largest salivary gland; paired
parotid duct is approx. 2 inches long, runs across masseter muscle, below zygomatic arch
duct pierces buccinator muscle to enter oral cavity opposite the upper second molar tooth
nerve supply: glossopharyngeal nerve (CN IX)

Question 29

mumps

Answer 29

parotitis (parotid inflammation)
painful swelling of the parotid glands; painful when chewing
contagious; viral infection
prevent - childhood vaccination
can be unilateral or bilateral

Question 30

blood supply of the face

Answer 30

common carotid artery divides into:
1. external carotid artery
2. internal carotid artery

external carotid artery gives branches ont he face:
facial artery
maxillary artery
superficial temporary artery

Question 31

facial artery

Answer 31

crosses the lower border of the mandible
within the face it has a tortuous course
it runs along the side of the nose to the medial angle of the eye

Question 32

facial pulse points

Answer 32

facial artery: over the mandible
superficial temporal artery: anterior to the ear

Question 33

venous drainage of the face

Answer 33

facial vein drains most of the face; runs with facial artery
superficial temporal vein drains the scalp
superficial temporal + maxillary veins drain into retromandibular vein joins facial vein which drains into internal jugular vein

Question 34

pathways for spread of infection from face to cavernous sinus

Answer 34

1. angular vein –> superior or inferior ophthalmic veins –> cavernous sinus
2. facial vein –> pterygoid plexus of veins –> cavernous sinus