Craniofacial Muscles (Muscles of Facial Expression)

Question 1

Occipitalis

Answer 1

occipitalis: lateral 2/3 of superior nuchal line; mastoid process
occipitalis: epicranial aponeurosis (Galea Aponeurotica)
occipitalis: draws scalp posteriorly
occipitalis: Posterior Auricular branch of VII

Question 2

Frontalis

Answer 2

frontalis: epicranial aponeurosis at coronal suture
frontalis: dermis and superficial fascia of frontal region & eyebrow

frontalis: elevates the eyebrows & skin at the nasal root OR draws the forehead down
in wrinkles

frontalis: Temporal branches of VII

Question 3

Temporoparietalis (variable)

Answer 3

temporalis fascia above auricle

lateral border of Galea aponeurotica

tenses the Galea

temporoparietalis: Temporal branches of VII

Question 4

Anterior Auriculares

Answer 4

temporalis fascia and epicranial aponeurosis

anterior portion of medial helix

draws auricle forward and upward

Temporal branch of VII

Question 5

Superior Auriculares

Answer 5

temporalis fascia and epicranial aponeurosis of VII

upper medial surface of auricle

elevates auricle

Posterior Auricular branch of VII

Question 6

Posterior Auriculares

Answer 6

base of mastoid process

lower anterior surface of auricle/convexity of concha

retracts & elevates auricle

Posterior Auricular branch of VII

Question 7

Corrugator supercilii

Answer 7

medial superciliary arch of frontal bone

dermis of medial eyebrow

draws eyebrows medially & inferiorly

Zygomatic and Temporal branches of VII

Question 8

Procerus

Answer 8

fascia over lower nasal bone & upper lateral nasal cartilage

dermis between eyebrows

draws medial angle
of eyebrows medially towards bridge of nose

Temporal, Zygomatic, and Buccal branches of VII

Question 9

Orbicularis oculi

Answer 9

ocular portion:
multiple origins from
nasal portion of
frontal bone; frontal
process of maxilla;
medial palpebral
ligament; arranged as a series of ellipses running from supero-medial to infero-medial; blending superiorly with frontalis and corrugator supercilii; inferiorly blending with levator labii superioris alequae nasi, levator labii superioris, and zygomaticus minor; laterally, blending with temporoparietalis portion of epicranius

ocular portion: dermis and superficial fascia or eyebrow

sphincter which narrows and closes the eyelids; draws eyelids slightly medially

Temporal, zygomatic and superior Buccal branches of VII

Question 10

Nasalis: a.compressor naris

Answer 10

canine eminence of maxilla

with contralateral muscle into aponeurosis on nasal cartilage

compresses external nasal aperture

Superior Zygomatic and Buccal branches of VII

Question 11

Nasalis: dilator naris

Answer 11

notch of maxilla over lateral incisor

alar cartilage

draws alae downward and laterally to flare nostrils & widen anterior nasal aperture

Zygomatic and Superior Buccal branches of VII

Question 12

Nasalis: depressor septi

Answer 12

incisive fossa of maxilla deep to orbicularis oris

moblile portion of nasal septum and posterior ala

widens anterior nasal aperture

Zygomatic and Superior Buccal branches of VII

Question 13

Levator labii superioris alaeque nasi

Answer 13

upper frontal process of maxilla

medial slip into greater alar cartilage of nose and overlying dermis; lateral slip into portion of upper lip, blending with levator labii superioris and orbicularis oris

medial slip: dilates nares and modivies circum-
malar sulcus
lateral slip: raises and everts upper lip; raises and deepens nasolabial sulcus

Zygomatic and Buccal branches of VII

Question 14

Levator labii superioris

Answer 14

lower rim of orbit
just above infraorbital foramen on maxilla and zygomatic

dermis of lateral 1⁄2 of upper lip between zygomaticus minor and #7

raises and everts upper lip & modifies nasolabial furrow

Zygomatic and Buccal branches of VII

Question 15

Levator anguli oris (Caninus)

Answer 15

canine fossa of maxilla below infraorbital foramen

modiolus lateral to angle of the mouth; intermingles with orbicularis oris, depressor anguli oris & zygomaticus major

raises angle of mouth & deepens
nasolabial furrow

Zygomatic and Buccal branches of VII

Question 16

Zygomaticus major

Answer 16

zygomatic portion of zygomatic arch

modiolus, lateral to angle of the mouth; dermis &mucosa of angle of mouth; intermingles with orbicularis oris, depressor anguli
oris & levator anguli oris

draws angle of mouth upward and laterally

Zygomatic and Buccal branches of VII

Question 17

Risorius (variable)

Answer 17

fascia over masseter & parotid gland (and angle of mouth superficial to platsyma)

skin & mucosa at angle of mouth

weak elevator of angle of the mouth

zygomatic and buccal branches of VII

Question 18

Zygomaticus minor

Answer 18

malar eminence just posterior to zygo- maticomaxillary suture

upper lip between zygomaticus major and levator
labii superioris

elevates upper lip, exposing maxillary teeth; assists in deepening nasolabial furrow

Zygomatic and Buccal branches of VII

Question 19

Depressor labii inferioris (quadratus labii inferioris)

Answer 19

oblique line of mandible,
deep to depressor anguli oris

dermis & mucosa
of lower lip, blending with contralateral muscle & with orbicularis oris

draws lower lip downward & slightly laterally

Mandibular Marginal and lower Buccal branches of VI

Question 20

Depressor anguli oris (traingularis)

Answer 20

linear origin from mental tubercle, along oblique line of mandible, continuous inferiorly with platysma; NOTE:
some medial fibers may cross the midline, interlacing with contralateral muscle
to form the
transverses menti (mental sling).

modiolus, blending with orbicularis oris and risorius

draws angle of mouth downward; stretches and flattens buccolabial sulcus and deepens mentolabial sulcus

Mandibular Marginal and Lower Buccal branches of VII

Question 21

Mentalis

Answer 21

incisive fossa of mandible

dermis of the chin

raises lower lip & soft tissue over mentum (active continuously, including sleep)

Mandibular Marginal branch of VII

Question 22

Orbicularis oris

Answer 22

This muscle encircles the mouth; organized into 4 largely indepen- dent quadrants: upper left, upper right; lower left and lower right, each comprised of a large pars peripheralis and a smaller pars marginalis (= 8 segments); origin: modiolus

blends with numerous muscles: upper periph with buccinator & depressor anguli oris; lower periph with buccinator, levator anguli oris & super- ficial part of zygo- maticus major; marginal fibers interlace in midline with contralateral muscle

sphincter of mouth;
draws lips together, draws corners of lips inward & either purses lips or
draws them against
teeth

Lower Zygomatic, Buccal and Mandibular Marginal branches of VII

Question 23

Buccinator

Answer 23

posterior alveolar process of maxilla
& mandible and superomedial surface of junction of body and ramus of mandible; pterygo- mandibular raphe

anterior fibers blend with depressor labii inferioris and depressor anguli oris.; both upper and lower fibers contribute to orbicularis oris but
do not decussate; continues to insert into dermis & mucosa of lips

flattens cheek against
teeth to resist lodging
of food/pooling of
liquid between cheek
and gum or expel air
from oral cavity; also, retracts buccolabial mucosa from teeth during mastication

Buccal branch of VII.

Question 24

Platysma

Answer 24

superficial fascia of antero-lateral neck

[mandibular portion: lower border of mandibular corpus
labial portion:
tissue of lateral 1⁄2
of lower lip between #13 and #14
modiolar portion: modiolus]

tenses superficial
fascia of antero-lateral neck; also: mandibular portion a weak depressor of the mandible &
labial portion a depressor of the lower lip

Cervical branch of VII