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Supralaryngeal Anatomy
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Muscles of Face
• Facial muscles are devoid of facial sheaths
(characteristic of skeletal muscle)
• Size, shape & extent of development depend
on
– age
– dentition
– sex
• Lips are most mobile
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Facial Muscles
Levator
Labii
Superioris
Risorius
Orbicularis
Oris
Depressor
Anguli
Mentalis
Oris
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Orbicularis Oris
• Principal muscle acting on the lips
• Oval ring of muscle encircling mouth
• Paired: upper & lower muscles (superior
& inferior), functional differentiation
• Acts as point of insertion for many other
muscles
• Function: Protrude & close lips,
compress, contract, extend, rounding 4
Obicularis Oris
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Buccinator
• “Bugler’s muscle”
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•
•
•
Lies deep to the risorius
Originates on the pterygomandibular ligament
Inserts into the lower orbicularis oris
Function: Compresses the lips & cheeks against
the teeth & draws the corners of mouth laterally;
primarily involved in mastication, moves food
onto grinding surface of the molars, contraction
constricts the oropharynx
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Buccinator
Pterygomandibular
Ligament
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Levator Anguli Oris
• Arises from the canine fossa of the
maxilla (lower part of orbit)
• Inserts into upper & lower lips
• Function: Draws the corner of the mouth
up and medial-ward (spreads lips)
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Levator Anguli Oris
Canine Fossa
of Maxilla
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Levator Labii Superioris
• Originates from the infraorbital margin
of the maxilla (lower part of orbit)
• Insertion into the mid-lateral region of
the upper lip
• Function: Elevation of the upper lip
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Levator Labii
Superioris
Infraorbital margin
of Maxilla
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Zygomatic Major
• Arises on the zygomatic bone
• Courses obliquely
• Inserts into the corner of the
obicularis oris
• Function: Elevates and retracts the
angle of the mouth, as in the gesture
of smiling
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Depressor Labii Inferioris
• Originates oblique line of mandible, runs
upward
• Insert into the lower lip and orbicularis
oris
• Function: Depresses the corners of the
mouth and, by virtue of attachment to
lower lip, help compress the lower lip to
the upper lip
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Depressor Labii
Inferioris
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Mentalis
• Origin from incisive fossa of mandible,
inserting into skin of chin below (lower
gum in area of mandibular teeth)
• Function: contraction elevates and
wrinkles the chin and pulls the lower lip
out
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Masseter
• Originates for zygomatic arch
• Insert into angle & lateral surface of the
ramus of the mandible
• Function: Closes jaw & retracts the
mandible
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Masseter
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Facial Muscles
• Obicularis oris, inferior & superior muscles:
– Lip protrusion, closure, retraction, elevation &
depression
• Risorius & Buccinator:
– Assist in retraction of the lips & support entrapment of
air within the oral cavity
• Levator labii superioris, zygomatic minor:
– Elevate upper lip
• Depressor labii inferioris:
– Depresses lower lip
• Zygomatic major:
– Elevates & contracts corners of mouth
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Muscles of the Mouth
• Extrinsic & intrinsic muscles of the
tongue
• Muscles for soft palate elevation
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Tongue
• Occupies the floor of the mouth
• Extrinsic muscles: moves tongue into different
positions or regions in the mouth
• Intrinsic muscles: Shapes tongue into contours;
fine graded control of the articulatory gestures
• Primarily involved in mastication & deglutition
– Movement of food
– Position food for chewing
– Propel it backward for swallowing
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Tongue
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•
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Dorsum: Superior surface
Tip or Apex: Anterior-most portion
Base: In oropharynx
Palatine surface: Portion of surface in
oral cavity; 2/3 of tongue
• Lingual Frenulum: Underside of tongue;
Joins inferior tongue & mandible;
stabilizing tongue during movement 21
Intrinsic Tongue Muscles
• Two pairs of muscles running
longitudinally, transversely & vertically
• Interact in a delicate fashion to produce
the rapid, delicate articulations for
speech & nonspeech activities
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Intrinsic Tongue Muscles
• Superior Longitudinal:
– Courses along the length of tongue
– Upper layer of tongue
– Originates from fibrous submucous layer near
epiglottis
– Fibers fan forward & outward to insert into the
lateral margins of the tongue & apex region
– Function: Elevate tongue tip, pulls tongue to one
side (toward side of contraction)
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Superior & Inferior Longitudinal Muscles
Superior
Inferior
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Intrinsic Tongue Muscles
• Inferior Longitudinal Muscle:
– Originates at the root of the tongue & corpus
hyoid
– Fibers course to apex of tongue
– Occupies lower sides of tongue (absent in
medial tongue base)
– Function: Depresses tongue tip; assist in
retraction of the tongue; Contraction to one side
pulls tongue in that direction & downward
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Intrinsic Tongue Muscles
• Transverse Muscles:
–Function: to narrow tongue; Pulls
edges toward midline
–Fibers originate at the median fibrous
septum & course laterally to insert into
side of the tongue
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Transverse & Vertical Muscles
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Intrinsic Tongue Muscles
• Vertical Muscles:
– Run at right angles to the transverse
muscles
– Course from base of tongue and insert into
the membranous cover
– Function: Flatten tongue; Pulls tongue
down into the floor of the mouth
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Intrinsic Tongue Muscles
Superior Longitudinal
Coronal
Vertical Muscles
Inferior Longitudinal
Transverse
Muscles
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Extrinsic Muscles
• Genioglossus:
– Prime mover, most of deeper bulk
– Arises from inner mandibular surface and fans
to insert into the tip & dorsum of the tongue
– Medial position
– Function:
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•
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•
1. Withdraw tongue into mouth
2. Pull tongue tip down, lower the tongue
3. Protrude the tongue
4. Pull tongue root & dorsum anteriorly
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Genioglossus
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Extrinsic Muscles
• Hyoglossus:
– Arises from greater cornu & lateral body
of the hyoid
– Inserts into the sides of the tongue between
the styloglossus & inferior longitudinal
– Function: Pulls sides of tongue down
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Hyoglossus
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Extrinsic Muscles
• Styloglossus:
– Originates from antero-lateral margin of
styloid process
– Inserts into inferior sides of tongue;
divides to insert into inferior longitudinal
& hyoglossus
– Function: Draws tongue back & up
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Styloglossus
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Extrinsic Muscles
• Palatoglossus:
– Muscle of the tongue & velum
– Function: Depress the soft palate or
elevating the back of the tongue
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Palatoglossus
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Velopharyngeal Anatomy
• Soft palate & its relationship with the
pharyngeal wall
• Muscles here run from skull and insert
somewhere in palate
• Muscles important for speech-Cleft palate
• Three sounds in English that require velum
to be depressed- n, m, ing
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Reading/Assignments
• Seikel: Pgs. 305-319
• Dickson: Pgs. 222-250
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