appendix 1 Muscles of facial expression

Muscle

Origin

Insertion

Action

Function

I. Forehead

Frontalis (s)

Galea aponeurotica

Skin of forehead and brow

Raises eyebrow;

Wrinkles forehead; used in

retracts scalp

frowning and to express

surprise and astonishment

II. Glabella

a. Corrugator supercilii (d)

Medial superciliary arch

Skin in the mid portion

Adducts and draws

Used to squint and protect eyes

(nasal process of

of brow

brow down

frontal bone)

b. Orbicularis oculi (s)

Medial and anterior

Surrounds orbital opening

Shuts eyelid

Wrinkles brow to produce

i. Orbital portion

orbital margin

as a sphincter: fibers are

a frown; used to wink,

over temple, cheek and

squint and protect eyes

into eyebrow

ii. Palpebral portion (s)

Medial palpebral ligament

Lateral palpebral raphe

Closes eye

Produces sphincteric action

involuntarily

of the eyelids

iii. Lacrimal portion (d)

Lacrimal crest

Upper and lower tarsal

Draws eyelids

Facilitates the lacrimal pump

plates

posteriorly

c. Depressor supercilii (s)

Nasal process of frontal

Skin of brow

Pulls down

Pulls eyebrows down, closes

bone

medial brow

eyelids, facilitates the

lacrimal pump

d. Procerus (s)

Nasal bone and cartilage

Skin of forehead between

Pulls down

Wrinkles central brow to

eyebrows

medial brow

produce frown; used to

squint and shield eyes

(conveys disdain or dislike)

III. Nose

a. Compressor naris

Canine eminence of

Nasal bridge aponeurosis

Compresses

Slows exhaled air

(transverse nasalis) (s)

maxilla

nasal aperture

b. Dilator naris

Maxilla above lateral

Nasal tip and alar skin and

Widens nasal

Prevents alar collapse in

(alar nasalis) (s)

incisor and alar cartilage

cartilage

aperture

forceful breathing; flares

nostrils during anger or

exertion

c. Depressor septi nasi (s)

Incisive fossa of maxilla

Lower nasal septum and

Draws nasal tip and

Narrows the nostrils

under surface of lower

alae downward

lateral alar cartilage

IV. Mouth

a. Orbicularis oris (s)

Medial maxilla, mandible

Mucous membrane of lips

Closes lips

Forms a sphincter around

and many muscles that

mouth; closes oral aperture;

converge around mouth;

protrudes, puckers and

deep surface or perioral

shapes lips (kissing); resists

skin; angle of the mouth

distension when blowing

(via modiolus)

b. Levator labii superioris

Frontal process of maxilla

Alar cartilage and

Dilates nares and

Deepens the upper nasolabial

alaeque nasi (s)

lateral upper lip

everts and elevates

fold, dilates nasal aperature

lateral upper lip

and used in scowling

c. Levator labii superioris

Lower margin of orbit,

Angle of mouth and

Elevates and everts

Used in expressing seriousness

(d and s)

above infraorbital

upper lip

upper lip

and sadness and deepens

foramen on maxilla

nasolabial fold

d. Zygomaticus minor

Malar surface of zygomatic

Upper lip at angle of

Draws mouth

Elevates and everts upper lip

(d and s)

bone (near maxillary

mouth into orbicularis

upward and

used in expressing sadness

suture line)

oris and levator labii

laterally

(see next above)

superioris

e. Zygomaticus major

Lateral surface of

Angle of mouth

Draws mouth

Elevates oral commissures used

(d and s)

zygomatic bone

(via modiolus)

upward and

in laughing or smiling

laterally

(bilateral); sneering and to

show disdain (unilateral)

f. Levator anguli oris (d)

Canine fossa below

Angle of mouth

Raises angle of

Widens oral aperature to grin

infraorbital foramen

(via modiolus) and

mouth and

or grimace and used in

of maxilla

upper lip musculature

lateral upper lip

smiling and laughing; it

deepens nasolabial furrow as

in contempt or disdain

g. Risorius (s)

Fascia of masseter,

Angle of mouth

Retracts angle of

Used in smiling and laughing

buccal skin and

(via modiolus)

mouth laterally

when present

parotid gland

(Continued)

268

BOTULINUM TOXINS IN CLINICAL AESTHETIC PRACTICE

(Continued)

Muscle

Origin

Insertion

Action

Function

h. Depressor anguli

Oblique line of mandible

Angle of mouth

Depresses angle of

Used in grimacing and

oris (s)

(via modiolus), upper

mouth downward

snarling; used in expressing

and lower lip

and laterally

sadness

i. Depressor labii

Between symphysis menti

Skin of lower lip and

Draws lower lip

Everts the lower lip, used in

inferioris (d)

and mental foramen;

orbicularis oris

downward and

drinking, pouting and

platysma

laterally

expressing irony; sorrow and

doubt

j. Mentalis (d)

Incisive fossa of mandible

Skin of chin

Raises and protrudes

Used in pouting and to elevate

(mentolabial sulcus)

lower lip and

skin of chin when expressing

wrinkles skin of chin

doubt or disdain

k. Buccinator (d)

Outer surface of mandible;

Angle of mouth (via modiolus);

Flattens cheek against

Presses cheek against molar

alveolar process of

upper and lower lips;

gums; used when

teeth; works with tongue to

maxilla and mandible;

interdigitates with

distending cheeks

keep food between occlusal

pterygomandubular

orbicularis oris

with air and

surfaces and out of oral

raphe

compresses them to

vestibule when chewing; used

force air out of

in sucking and to puff up

mouth

cheeks and blow air out of

the mouth as when blowing

up a balloon or playing a

wind instrument

l. Platysma (s)

Pectoralis fascia of second

Lower jaw, angle of mouth

Widens mouth

Used in expressing horror,

to fourth rib, deltoid

(via modiolus), parotid

aperture at

tension and stress; assists in

fascia and subcutaneous

fascia, skin of cheek and

commissures; pulls

shaving or in relieving

tissue of infraclavicular

lower lip; orbicularis oris

skin of lower face

pressure of a tight collar; and

and supraclavicular

and neck taught

depresses lower lip and

regions

mandible against resistance

Frontalis

Procerus and transverse

Alar part of levator labii

part of nasalis

superioris alaeque nasi

and alar part of nasalis

Buccinator and orbicularis oris

Levator labii superioris alaeque

Risorius and orbicularis oris

Levator labii superioris alaeque

nasi and levator labii superioris

nasi and zygomaticus minor

MUSCLES OF FACIAL EXPRESSION

269