Facial Associated Muscles

Lab 4

Nasalis

Nasalis

Nasalis origin

maxilla

Nasalis insertion

nasal bone

Nasalis function

elevates nostrils laterally (flares)

opens/maintains nostril opening

Nasalis nerve innervation

buccal nerve of facial nerve (CNVII)

Zygomaticus major

Zygomaticus major origin

temporal process of zygomatic bone

Zygomaticus major insertion

modiolus at the angle of mouth (corner of mouth)

Zygomaticus major function

elevates corners of mouth (smiling) superiorly and posteriorly

Zygomaticus major nerve innervation

buccal and zygomatic branches of facial nerve (CNVII)

Zygomaticus minor

Zygomaticus minor origin

lateral surface of zygomatic bone

Zygomaticus minor insertion

modiolus at the angle of mouth (corner of mouth)

Zygomaticus minor function

elevates lip with zygomaticus major (smiling)

Zygomaticus minor nerve innervation

buccal and zygomatic branches of facial nerve (CNVII)

Risorius

Risorius origin

varies, muscle not always present

Risorius insertion

modiolus at the angle of mouth (corner of mouth)

Risorius function

retracts angle of mouth laterally (smiling)

Risorius nerve innervation

buccal branch of facial nerve (CNVII)

Levator labii superioris

Levator labii superioris origin

zygomatic process of maxilla

Levator labii superioris insertion

orbicularis oris of upper lip

Levator labii superioris function

elevates lip with zygomaticus major (smiling)

Levator labii superioris nerve innervation

buccal and zygomatic branches of facial nerve (CNVII)

Orbicularis oculi

Orbicularis oculi origin

medial orbit; frontal, lacrimal, maxilla bones

Orbicularis oculi insertion

skin of the upper eyelid

Orbicularis oculi function

depresses upper eyelid, closing/squinting eyelid

Orbicularis oculi nerve innervation

temporal and zygomatic branches of facial nerve

Levator palpebrae superioris

Levator palpebrae superioris origin

lesser wing of sphenoid bone

Levator palpebrae superioris insertion

skin of the upper eyelid

Levator palpebrae superioris function

elevates superior eyelid, widening eye

Levator palpebrae superioris nerve innervation

oculomotor nerve (CNIII)

Superior rectus

Superior rectus origin

common tendinous ring

Superior rectus insertion

superior eyeball

Superior rectus function

rotates eye supriorly

Superior rectus nerve innervation

oculomotor nerve (CNIII)

Inferior rectus

Inferior rectus origin

common tendinous ring

Inferior rectus insertion

inferior eyeball

Inferior rectus function

rotates eye inferiorly

Inferior rectus nerve innervation

oculomotor nerve (CNIII)

Medial rectus

Medial rectus origin

common tendinous ring

Medial rectus insertion

medial eyeball

Medial rectus function

rotates eye medially

Medial rectus nerve innervation

oculomotor nerve (CNIII)

Lateral rectus

Lateral rectus origin

common tendinous ring

Lateral rectus insertion

lateral eyeball

Lateral rectus function

rotates eye laterally

Lateral rectus nerve innervation

abducens nerve (CNVI)

Superior oblique

Superior oblique origin

sphenoid bone

Superior oblique insertion

superolateral aspect of eyeball

Superior oblique function

rotates eye laterally and inferiorly

Superior oblique nerve innervation

trochlear nerve (CNIV)

Inferior oblique

Inferior oblique origin

maxilla

Inferior oblique insertion

inferolateral aspect of eyeball

Inferior oblique function

rotates eye laterally and superiorly

Inferior oblique nerve innervation

oculomotor nerve (CNIII)

Orbicularis oris

Orbicularis oris origin

medial maxilla and mandible, and modiolus

Orbicularis oris insertion

skin and tissue of the lips

Orbicularis oris function

closes and protrudes lips (kissing)

Orbicularis oris nerve innervation

buccal branch of facial nerve (CNVII)

Masseter

Masseter origin

zygomatic process of maxilla and zygomatic arch

Masseter insertion

ramus/angle of mandible

Masseter function

elevates/closes mouth (chewing)

Masseter nerve innervation

mandibular branch of trigeminal nerve (CNV)

Buccinator

Buccinator origin

alveolar processes of maxilla and mandible

Buccinator insertion

modiolus at the angle of mouth

Buccinator function

compresses cheeks medially

Buccinator nerve innervation

buccal branch of facial nerve (CNVII)

Depressor anguli oris

Depressor anguli oris origin

oblique line of mandible

Depressor anguli oris insertion

modiolus at the angle of mouth

Depressor anguli oris function

depresses lower lip inferiorly and laterally

Depressor anguli oris nerve innervation

buccal and mandibular branches of facial nerve

Depressor labii inferioris

Depressor labii inferioris origin

oblique line of mandible

Depressor labii inferioris insertion

skin of the lower lip

Depressor labii inferioris function

depresses lower lip inferiorly and laterally

Depressor labii inferioris nerve innervation

mandibular branches of facial nerve

Mentalis

Mentalis origin

incisive fossa of mandible

Mentalis insertion

skin of the chin

Mentalis function

elevates, everts, and protrudes lower lip

Mentalis nerve innervation

mandibular branches of facial nerve

Platysma

Platysma origin

connective tissue layering the clavicle

Platysma insertion

lower border of mandible and associated muscles

Platysma function

depresses mandible and angle of mouth, tenses skin of lower face and anterior neck

Platysma nerve innervation

cervical branch of facial nerve (CNVII)