Myology
Muscles of the Face
Muscles of Facial Expression
Eye Muscles
• Orbicularis oculi
– Under both conscious/unconscious control i.e. blinking
– When entire muscle is contracted eyelids & surrounding
area will be drawn medially decreasing amount of light
entering eye
• Levator palpebrae superioris
– Attaches from sphenoid bone to upper eyelid.
– Nerve memory hint: columns (CN III) opens the eye.
• Corrugator supercilii
– Draws eyebrows inferiorly/medially as in frowning
causing vertical wrinkles superomedially to eye.
2
Orbicularis Oculi
O: Medial side of eye
I: Medial side of eye (returns
to same attachment
encircling the eye)
A: Closes & squints the
eye. Also assists in tear
transport and drainage
N: CN VII (Facial nerve)
Palpation: page 35
3
Levator Palpebrae Superioris
O: Sphenoid Bone
I: Upper Eyelid
A: Elevates upper eyelid
N: CN III (Oculomotor nerve)
Palpation: page 38
4
Corrugator Supercilii
O: Inferior frontal bone
I: Skin deep to medial eyebrow
A: Draws eyebrow inferomedially
N: CN VII (Facial nerve)
Palpation: page 40
5
Muscles of Facial Expression
Nose Muscles
• Procerus
– Often blends with frontalis superiorly and nasalis
inferiorly
– Gives look of frowning and also helps shield eyes from
bright light
– Person may convey air of superiority (hence “procerus”
meaning chief, noble or prince).
• Nasalis
– Transverse part sometimes called compressor nasi and
alar part dilatator nasi
– Blends with procerus superiorly
• Depressor Septi Nasi
– Sometimes considered part of alar portion of nasalis
6
Procerus
O: Fascia over nasal bone
I: Skin between eyebrows
A: Draws down medial
eyebrows. Also wrinkles
the skin of the nose
N: CN VII (Facial nerve)
Palpation: page 42
7
Nasalis
O: Maxilla
I: Cartilage of Nose and
Opposite side Nasalis
muscle
A: Flares nostrils
N: CN VII (Facial nerve)
Palpation: page 44
8
Depressor Septi Nasi
O: Incisive fossa of the
maxilla
I: Cartilage of Nose
A: Constricts nostrils
N: CN VII (Facial nerve)
Palpation: page 46
9
Muscles of Facial Expression
Mouth Muscles
• Levator Labii Superioris
– Main elevators of upper lip are levator labii superioris &
zygomaticus minor.
– Contraction alone will elevate upper lip as in showing
someone our upper teeth.
• Zygomaticus Minor
– Blends with levator labii superioris
• Zygomaticus Major
– Contributes to smiling and laughing
– 6 muscles attach into modiolus (fibro muscular condensation
≈ ¼” lateral to angle of mouth): zygomaticus major, levator
anguli oris, risorius, depressor anguli oris, buccinator, &
orbicularis oris.
Levator Labii Superioris
O: Inferior orbital margin of
the maxilla
I: Upper Lip
A: Elevation of Upper Lip
N: CN VII (Facial nerve)
Palpation: page 51
Zygomaticus Minor
O: Zygomatic bone
I: Upper Lip
A: Elevation of Upper Lip
N: CN VII (Facial nerve)
Palpation: page 54
Zygomaticus Major
O: Zygomatic bone
I: Angle of Mouth
A: Elevation of Angle of
Mouth as in smiling.
Also draws laterally at the
angle of the mouth
N: CN VII (Facial nerve)
Palpation: page 57
Muscles of Facial Expression
Mouth Muscles
• Levator Anguli Oris
– Also known as the caninus because contraction
can result in teeth especially canine tooth
becoming visible – “Dracula” expression.
– Contraction alone can manifest a sneer.
Levator Anguli Oris
O: Maxilla, just inferior to
the infraorbital foramen
I: Angle of Mouth
A: Elevation of Angle of
Mouth
N: CN VII (Facial nerve)
Palpation: page 60
Muscles of Facial Expression
Mouth Muscles
• Risorius
– Drawing angle of mouth laterally is involved
with grinning, smiling, and laughing.
• Depressor Anguli Oris
– Blends into the platysma
– Contribute to facial expression of sadness or
uncertainty.
• Depressor Labii Inferioris
– Contribute to facial expressions of sorrow,
doubt, and irony.
Risorius
O: Fascia Superficial to
Masseter
I: Angle of Mouth
Action: Draws Laterally the
Angle
of Mouth
N: CN VII (Facial nerve)
Palpation: page 63
Depressor Anguli Oris
O: Mandible
I: Angle of Mouth
A: Depresses the Angle of
Mouth. Also assists the
risorius in drawing the
angle of the mouth
laterally
N: CN VII (Facial nerve)
Palpation: page 66
Depressor Labii Inferioris
O: Mandible
I: Lower Lip
A: Depression of Lower Lip.
Also assists in drawing the
lower lip laterally and
everting it.
N: CN VII (Facial nerve)
Palpation: page 69
Muscles of Facial Expression
Mouth Muscles
• Mentalis
– Contributes to facial expressions of doubt, pouting, or disdain
• Buccinator
– Parotid duct pierces through buccinator to enter mouth
– Action of compressing the cheeks against the teeth by the 2
buccinators working bilaterally is important for forcefully expelling air
from the mouth.
• Latin word for trumpeter is “buccinator”
– Important with whistling, blowing up a balloon and with helping keep
food from lingering in vestibule of mouth.
– Contributes to expression (puckering the cheeks) made when person
eats something sour.
• Orbicularis Oris
– Causes kips to close and protrude as in puckering lips or whistling.
Mentalis
O: Mandible
I: Skin of the Chin
A: -Elevation of Lower Lip
-Eversion and Protracts the
Lower Lip
- Wrinkles the skin of the chin
N: CN VII (Facial nerve)
Palpation: page 72
Buccinator
O: Maxilla and Mandible
I: Lips (buccinator muscle is
located in the tissue of the
cheek)
A: Compression of Cheeks
(against teeth)
N: CN VII (Facial nerve)
Palpation: page 75
Orbicularis Oris
O: Surrounds the mouth
Action: Closes mouth and
protracts the lips
N: CN VII (Facial nerve)
Palpation: page 77