Facial Nerve and Muscles of Facial Expression Flashcards
Lecture 3
the facial nerve enters through the
petrous part of the temporal bone through the internal auditory meatus
after passing through the internal auditory meatus, the facial nerve then passes through
the petrous temporal bone within the facial canal
the facial nerve exits the skull through
the stylomastoid foramen, behind the ear
after the facial nerve exits the skull the nerve then enters the
parotid gland on the face
within the parotid gland the facial nerve divides into
5 motor branches that innervate muscles of facial expression
branches of the facial nerve
temporal
zygomatic
buccal
marginal mandibular
cervical
motor fibres in the facial nerve supply
muscles of facial expression
several other muscles: digastric muscle, stylohyoid and stapedius muscle
general sensory fibres in the facial nerve supply
skin of the external ear (posterior auricular nerve)
special sensory of taste fibres in the facial nerve carry
taste sensation from the anterior 2/3 of the tongue via chorda tympani branch
parasympathetic fibres in the facial nerve supply
lacrimal gland (produces tears)
submandibular and sublingual salivary glands
frontalis muscles
originates from the membrane (aponeurosis) in the scalp
inserts into the skin at eyebrows and root of the nose
expression - surprise
orbicularis oculi
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
orbicularis oris
circular muscle around the mouth
closes/compresses the lips
most muscles in the mouth region insert into orbicularis oris
buccinator muscle
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
muscles of the upper lip
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
muscles of the lower lip
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
mentalis muscle
short, thick muscle at the tip of the chin
raises the skin of chin
platysma muscle
very thin muscular sheet in the neck
originates in the skin over clavicle
inserts to the lower border of the mandible
shaving muscle
occipitalis muscle
muscle of facial expression on the back of the head
attaches to the occipital bone
inserts into the aponeurosis in the scalp
masseter muscle
not a muscle of facial expression
it is a muscle of mastication
temporal branch innervation
frontalis
zygomatic branch innervation
orbicularis oculi
buccal branch innervation
buccinator, zygomaticus major, levator labii superiors, levator anguli oris
marginal mandibular innervation
depressors labii inferiors, depressor anguli oris, mentalis