Lecture 6 Muscles of Scalp and Face

add insertion of muscles later

remind myself

what does the occipitofrontalis muscle consist of

it has two frontal bellies anteriorly, two occipital bellies posteriorly, and an aponeurotic tendon (epicranial aponeurosis) connecting the four bellies.

are the frontal bellies of the occipitofrontalis muscle in anterior or posterior side

anterior

are the occipital bellies of the occipitofrontalis muscle in anterior or posterior side

posterior

what structure connects the four bellies in the occipitofrontalis muscle

aponeurotic tendon (epicranial aponeurosis)

origin of the frontal belly in occipitofrontalis muscle

skin and superficial fascia of eyebrow

origin of the occipital belly in occipitofrontalis muscle

highest nuchal line of occipital bone

function of occipital belly and frontal belly

moves scalp on skull and raises eyebrows

nerve supply of occipital and frontal belly

facial nerve

name the nerve supply of the scalp that is anterior to the ears and the vertex

Supratrochlear nerve (CNV1), Supraorbital nerve (CNV1), Zygomaticotemporal nerve (CNV2), Auriculotemporal nerve (CNV3)

which section of the scalp does Supratrochlear nerve (CNV1) supply to

anterior to the ears and the vertex

which section of the scalp does Supraorbital Nerve (CNV1) supply to

anterior to the ears and the vertex

which section of the scalp does Zygomaticotemporal Nerve (CNV2) supply to

anterior to the ears and the vertex

which section of the scalp does Auriculotemporal Nerve (CNV3) supply to

anterior to the ears and the vertex

name the nerve supply of the scalp that is posterior to the ears and the vertex

less occipital nerve, greater occipital nerve, and by branches of all four divisions of the spinal cutaneous nerves (C2 and C3)

which section of the scalp does lesser occipital nerve supply to

posterior to the ears and the vertex

which section of the scalp does greater occipital nerve supply to

posterior to the ears and the vertex

what are the arterial supply of the scalp

internal carotid arteries and external carotid arteries

which branch of the internal carotid arteries provide arterial supply to the scalp

supratrochlear arteries and supraorbital arteries

which branch of the external carotid arteries provide arterial supply to the scalp

Superficial temporal arteries (anterior to the ear), Posterior auricular arteries, Occipital arteries

what veins are responsible for the venous drainage of the scalp

occipital vein, posterior auricular vein, external jugular vein, posterior external jugular vein, retromandibular vein, facial vein, internal jugular vein

what are the lymph nodes that contribute to the lymphatic drinage of the scalp

occipital, mastoid (retroauricular), parotid, buccal, submental, submandibular, jugulo-omophyoid, superficial cervical, deep cervical

facial muscles are mainly two types based on what

insertion

two types of insertion of facial muscles

insert to bone (helps in bone movement) and insert to the skin (plays role in facial expression)

facial muscles mainly divided into …?

muscle of facial expression and muscle of mastication/chewing

muscles of facial expression are divided into what groups

orbital group, nasal group, oral group, and other muscle groups

what are the three muscles in the orbital group of muscles of the facial expression

orbicularis oculi, corrugator supercilii, depressor supercilli

orbicularis oculi, corrugator supercilii, depressor supercilli are part of which group

orbital group

three parts of the orbicularis oculi

orbital part (outer), palpebral part (inner), lacrimal part (small)

function of orbital part (outer) of the orbicularis oculi

action - close the lids tightly

function of palpebral part (inner) of the orbicularis oculi

action - close the lids gently

function of lacrimal part (small) of the orbicularis oculi

action - dilate lacrimal sac

what is lagophthalmos

incomplete eyelid closure

what is the term for incomplete eyelid closure

lagophthalmos

what happens if lagophthalmus is untreated

can cause dry cornea and conjunctiva, and eventually infection

origin of corrugator supercilii

superciliary arch

which muscle is originated from superciliary arch

corrugator supercilii

action of corrugator supercilii

produce vertical wrinkles of the forehead in frowning as expression of annoyance

name the muscle that produce vertical wrinkles of the forehead in frowning as expression of annoyance

corrugator sueprcilii

origin of Depressor Supercilli

medial orbital margin and adjacent nasal bone

which muscle originates from medial orbital margin and adjacent nasal bone

Depressor Supercilli

action of Depressor Supercilli

depresses the medial part of the eyebrow, producing a downward movement associated with frowning or concentration expressions

name that muscle that depresses the medial part of the eyebrow, produces a downward movement associated with frowning or concentration expressions

depressor supercilli

three main muscles of the nasal group of muscles of the facial expression

nasalis, procerus, depressor septi nasi

nasalis, procerus, depressor septi nasi are part of which group

nasal group

two main parts of nasalis in nasal group

transverse part (compressor naris/nasalis traverse) and alar apart (dilator naris/nasalis alar)

transverse part (compressor naris/nasalis traverse) and alar apart (dilator naris/nasalis alar) are part of what structure in the nasal group

nasalis

action of nasalis transcompressor naris/nasalis traverse

Compresses the mobile nasal cartilages

action of dilator naris/nasalis alar

Widens the nasal aperture (by pulling the alar laterally) in deep inspiration and the upper lip moves up during this process

which structure indicates a sign of anger when acted upon

dilator naris/nasalis alar

origin of procerus

nasal bone and lateral nasal cartilage

which muscle originates from the nasal bone and lateral nasal cartilage

procerus

action of procerus

pulls down the medial end of the eyebrow and wrinkles the skin of the nose transversely in frowning

what muscle does pulling down the medial end of the eyebrow and wrinkling the skin of the nose transversely in frowning correspond to

procerus

origin of depressor nasi septi

incisive fossa of the maxilla

which muscle originates from incisive fossa of the maxilla

depressor nasi septi

action of depressor nasi septi

depresses the nasal septum upon contraction and constrict the aperture of the nostril

which muscle is responsible for depressing the nasal septum upon contraction and constricting the aperture of the nostril

depressor nasi septi

name the groups in the oral group that move the lips and cheek

orbicularis oris, buccinator, lower group of oral muscles and upper group of oral muscles

orbicularis oris, buccinator, lower group of oral muscles and upper group of oral muscles are part of which group

oral group

function of orbicularis oris

close the mouth

which structure help close our mouth

orbicularis oris

action of buccinator

aids in mastication by prevent accumulation of food in vestibule of mouth

which muscle aids in mastication by prevent accumulation of food in vestibule of mouth

buccinator

list the muscles in the lower group of oral muscles

depressor anguli oris, depressor labii inferioris, mentalis

depressor anguli oris, depressor labii inferioris, mentalis correspond to which group of muscles

lower group of oral muscles

function of lower group of oral muscles

depressing the lower lip

which group of muscles is responsible for depressing the lower lip

lower group of oral muscles

list the muscles in the upper group of oral muscles

zygomaticus major, zygomaticus minor, levator labii superioris, levator anguli oris, risorius

zygomaticus major, zygomaticus minor, levator labii superioris, levator anguli oris, risorius, correspond to which group of muscles

upper group of oral muscles

function of upper group of oral muscles

elevating and everting the upper lip

which group of muscle is responsible for elevating and everting the upper lip

upper group of oral muscles

what are the other muscle groups of our facial expressions

platysma, auricular (superior, anterior, posterior)

four muscles in the muscles of mastication

masseter, temporalis, lateral pterygoid muscle and medial pterygoid muscle

masseter, temporalis, lateral pterygoid muscle and medial pterygoid muscle correspond to what muscles

muscles of mastication

primary function of the muscles of mastication

close the mouth

function of masseter and temporalis

Move the upper teeth against the lower teeth in a grinding action during mastication

what structures move the upper teeth against the lower teeth in a grinding action during mastication

masseter and temporalis

function of lateral and medial pterygoid muscle

move the jaw sideways to grind the food

which muscle help move the jaw sideways to grind the food

lateral and medial pterygoid muscle

Muscles of mastication are innervated by what nerve

mandibular division of the trigeminal nerve (cranial nerve V3)

Muscles of facial expression are innervated by what nerve

facial nerve (cranial nerve VII)

mandibular division of the trigeminal nerve (cranial nerve V3) innervates what muscle

Muscles of mastication

facial nerve (cranial nerve VII) innervates what muscle

muscle of facial expression

name the branches of the facial nerve

temporal, zygomatic, buccal, marginal mandibular, cervical

what structure is part of the temporal brunch of the facial nerve

frontalis, orbicularis oculi, corrugator supercilii

what structure is part of the zygomatic brunch of the facial nerve

orbicularis oculi

what structure is part of the buccal brunch of the facial nerve

orbicularis oris, buccinator, zygomaticus

what structure is part of the marginal mandibular brunch of the facial nerve

mentalis, depressor labii inferioris, depressor anguli oris

what structure is part of the cervical brunch of the facial nerve

platysma