Gross Anatomy U4L32 Face and Scalp

bones of the superficial face

neurocranium

viscerocranium

neurocranium

frontal bone

contributes to forehead, brow ridge

vicerocranium

nasal, maxilla, zygomatic, mandible

vomer, lacrimal, inferior nasal concha and palatine bones are deeper

glabella

area between the eyebrows with vertical creases (wrinkles)

orbit

parts of the frontal, maxilla, zygomatic, and lacrimal bones contribute to the orbit

supraorbital margin

the brow ridge, the hairy eyebrows help with expressions

eyelids

superior and inferior palpebrae

palpebral fissure

opening between eyelids to allow light to eye

medial and lateral canthi

corners where upper and lower eyelids meet

what forms the external nose

nasal bones

cartilage: septal, lateral, alar

external naris (nostrils)

lateral expansions (alae)

dorsum (bridge) of nose

what makes up the oral region

lips

philtrum

chin

lips

external area where mucosa of oral cavity meets skin of the face

philtrum

midline groove between nose septum and mouth

chin

humans are the only animal with a protruding and developed chin

temporal region

lateral region of face, posterior to orbits, anterior to ears

superficial temporal vessels

visible, usually the throbbing arteries when someone is angry

what nerve innervates all muscles of facial expression

facial nerve (CN VII) via parotid plexus

orbital group involves what

moves skin surrounding the eyes

orbicularis oculi

circular muscles (sphincter) close the eyelids

three parts of the orbicularis oculi

orbital

palpebral

lacrimal

orbital part of the orbicularis oculi

orbital margin to medial palpebral ligament, strong closure

palpebral part of the orbicularis oculi

medial palpebral ligament to lateral palpebral raphe, gentle closure (wink)

facial nerve pathway

exits stylomastoid foramen via internal acoustic meatus, middle ear

5 main branches of facial nerve

temporal, zygomatic, buccal, marginal mandibular, cervical

lacrimal part of the orbicularis oculi

posterior to medial palpebral ligament

facilitates tear pump into lacrimal sac

corrugator supercilli

spans frontal (supraorbital ridge) to middle of eyebrow

draws medial eyebrows inferomedially

stern, angry, focused expressions >:I

groups of facial expression muscles

orbital group

oral group

nasal group

other facial muscles

oral group

moves facial skin surrounding the mouth

muscles of the oral group

levator labii superioris

levator labii superioris alaeque nasi

zygomaticus minor

zygomaticus major

risorius

buccinator

levator anguli oris

depressor anguli oris

depressor labii inferioris

mentalis

orbicularis oris

levator labii superioris

spans from maxilla near inferior orbit to lips

deep to orbicularis oculi to upper lip

elevates upper lip

levator labii superioris alaeque nasi

spans from maxilla to cartilage of nose and lateral upper lip

elevates upper lips and/or dilates nostil

zygomaticus minor

spans from zygomatic bone (anteromedial to the major) obliquely to lateral upper lip

elevates upper lip

zygomaticus major

spans from zygomatic bone obliquely to corner of mouth

pulls mouth superolaterally when smiling

risorius

spans from parotid fascia and buccal skin to corner of mouth

widens mouth transversely

buccinator

spans from pterygomandibular raphe, maxilla, mandible to mouth

pulls cheeks medially, compresses against the teeth, aids in sucking

levator anguli oris

spans from canine fossa of maxilla (deep to levator labii superioris) to angle of mouth

elevates upper lip at an angle

depressor anguli oris

spans from mandible anterior margin to corner of mouth

depresses lower lips outwardly at an angle

depressor labii inferioris

spans from mandible anterior margin to lower lip

depresses lower lip

orbicularis oris

circulator muscular deep to lips

interlaced with buccinator and other oral mscles

closes mouth, purses and protrudes lips “kissing muscle”

nasal group muscle