Week 6/7: Muscle of facial expressions, pharynx, tongue and soft palate

facial paralysis

inability to form facial expressions on 1 side of face; can be temp or permanent; may indicate damage to cranial nerve VII (facial nerve)

orbicularis oris muscle

acts to shape and control the size of the mouth opening and lip positions and movement during speech

epicranial muscle

one of the layers that form the scalp; 2 bellies - frontal, occipital

epicranial - frontal belly origin

form epicranial aponeurosis; no bony attachment

epicranial muscle - occipital belly origin

from superior nuchal line and mastoid process

epicranial muscle - frontal belly insertion

to the skin of the eyebrow and root of nose

epicranial muscle - occipital belly insertion

into the epicranial aponeurosis

epicranial aponeurosis

large, spread-out scalpel tendon, separate the bellies, most superior part of the skull

raises eyebrows

what is action of epicranial muscle?

orbicularis oculi muscle

encircles the orbit; functions to protect and moisten the eye, loss of function dry eyes

orbicularis oculi muscle - origin

orbital rim, nasal process of the frontal bone, forntal process of the maxilla

orbicularis oculi muscle - insertion

skin at the lateral canthus (crows feet), some fibers encircle the orbit

closes eyelid - squnting

what is the action of orbicularis oculi muscle?

corrugator supercilii muscle

deep to the superior part of the orbicularis oculi muscle

corrugator supercilii muscle - origin

the frontal bone in the supraorbital region

corrugator supercilii muscle - insertion

into the skin of the eyebrow

frowning

what is the action of corrugator supercilii muscle?

orbicularis oris muscle

acts to shape and control the size of the mouth opening and lip positions and movement during speech

orbicularis oris muscle - origin

facial modiolus - at labial commissure, vermillion zone fibers encircle the mouth between the skin and labial mucosa with no bony attachment

orbicularis oris muscle - insertion

skin of the lips at the labial commissures - upper lip also at ridges of philtrum

pressing, tightening/thinning, rolling inward, thrusting outward

what is the action of orbicularis oris muscle?

buccinator muscle

thin quadrilateral muscle; forms anterior part of cheek/lateral wall within the buccal mucosa

buccinator muscle - origin

alveolar process of maxilla, alveolar process of mandible, pterygoidmandibular raphe

buccinator muscle - insertion

at labial commissures - muscle fibers interact and take on a braided effect

trumpet muscle; keeps food pushed posterior

what is the action of buccinator muscle?

risorius muscle

thin muscle

risorius muscle - origin

fascia superficial to the masseter muscle

risorius muscle - insertion

into the skin at the ipsilateral labial commissure of the facial modiolus

smiling/grinning - grimace

what is action of risorius muscle?

levator labii superioris alaeque nasi muscles - origin

frontal process of maxilla

levator labii superioris alaeque nasi muscles - insertion

skin of the ala of the nose and upper lip

sneering

what is action of levator labii superioris alaeque nasi muscles?

levator labii superioris muscles

broad flat muscle

levator labii superioris muscles - origin

infraorbital rim of maxilla

levator labii superioris muscles - insertion

skin of upper lip

elevates upper lip

what is action of levator labii superioris muscles?

zygomaticus minor muscles

small variable muscle

zygomaticus minor muscle - origin

body of the zygomatic bone

zygomaticus minor muscle - insertion

skin of the upper lip beside levator labii superioris

smiling

what is action of zygomaticus minor muscle?

levator anguli oris muscles

deep to both zygomatic major and minor muscles

levator anguli oris muscle - origin

canine fossa of max, superior to the root of max canine

levator anguli oris muscle - insertion

skin at the ipsilateral labial commissure, along with zygomaticus major, depressor anguli oris and orbicularis oris muscles

smiles

what is action of levator anguli oris muscle?

zygomaticus major muscles

located lateral to the zygomatic minor muscle

zygomaticus major muscle - origin

zygomatic bone

zygomaticus major muscle - insertion

skin at the ipsilateral labial commissure at the facial modiolus in and around the orbicularis oris

smiling lateral

what is action of zygomaticus major muscle?

depressor anguli oris muscle

triangular muscle

depressor anguli oris muscle - origin

inferior border of the mandible

depressor anguli oris muscle - insertion

skin at the ipsilateral labial commissure at the facial modiolus (same as risorius)

frowns

what is action of depressor anguli oris muscle?

depressor labii inferioris muscle

deep to depressor anguli oris muscle; small quadrilateral muscle

depressor labii inferioris muscle - origin

inferior border of the mandible

depressor labii inferioris muscle - insertion

skin of lower lip

depresses lower lip - shows mand incisors

what is action of depressor labii inferioris muscle?

mentalis muscle

short thick muscle, medial to mental nerve

mentalis muscle - origin

mandible near midline

mentalis muscle - insertion

skin of the chin

raises chin, lower lip protrudes, narrows mandibular vestibule

what is action of mentalis muscle?

platysma muscle

from the neck to mouth superficial to anterior cervical triangle and external jugular vein

platysma muscle - origin

in skin superficial to clavicle and shoulder

platysma muscle - insertion

inferior border of the mandible and other muscles surrounding the mouth

raises skin of neck

what is action of platysma muscle?

tongue

thick vascular mass of voluntary muscle; anchored to floor of mouth by lingual frenum; divided in equal halves by median septum

intrinsic group

changes shape of the tongue; 4 pairs

extrinsic group

move tongue while suspending and anchoring the tongue to structures of the mandible, styloid process and hyoid bone; 3 pairs

superior longitudinal, transverse, vertical, inferior longitudinal

what are the 4 pairs of intrinsic tongue muscles?

superior longitudinal muscle

most superficial, runs oblique/longitudinal, close to dorsal surface from base to apex

transverse muscle

deep to superior longitudinal, runs transverse from median septum to lateral border

vertical muscle

runs vertical from dorsal to ventral surface

inferior longitudinal muscle

close to ventral surface, runs longitudinal from base to apex

styloglossus, genioglossus, hypoglossus

what are the 3 pairs of extrinsic tongue muscles?

styloglossus muscle

origin styloid process insert into lateral surface of the tongue, border between the body and the base; retracts tongue superiorly and posteriorly

genioglossus muscle

fan-shaped, largest extrinsic muscle - origin genial tubercles, inferior fibers insert on hyoid bone; divided by median septum - action to protrude and stick out tongue

hypoglossus muscle

originates on both the greater cornu and body of hyoid; inserts in the lateral surface of body; depresses tongue

pharyngeal muscles

involved in speaking, swallowing and middle ear function; responsible for initiating the swallowing process; part of respiratory and digestive systems; connected to nasal and oral cavity

stylopharyngeus muscle

paired longitudinal muscle; originates from styloid process and inserts in the lateral and posterior pharyngeal walls; elevates and widens pharynx

pharyngeal constrictor muscles

forms lateral and posterior walls of larynx; 3 paired muscles - superior, middle, inferior; muscles overlap each other

superior pharyngeal constrictor

origin - hamulus, mandible and pterygomandibular raphe; attached to buccinator muscle at pterygomandibular raphe

middle pharyngeal constrictor

origin on the hyoid bone and stylohyoid ligament

inferior pharyngeal constrictor

origin from thyroid and cricoid cartilage of larynx; most superficial of all three

soft palate

5 paired muscles; forms non bony area of roof of the mouth or oropharynx and connects laterally with the tongue

palatoglossus muscle

forms anterior faucial pillar, anterior to the palatine tonsils; origin - posterior of median palatine raphe; inserts - lateral surface of the tongue

palatopharyngeus muscle

forms posterior faucial pillar, posterior to each palatine tonsil; origin - soft palate; inserts - walls of the laryngopharynx and thyroid cartilage

levator veli palatini muscle

superior to soft palate; origin - inferior surface of the temporal bone; inserts - medial palatine raphe

tensor veli palatini muscle

special ribbon like muscle of the palate; active during all movements of the soft palate; responsible for opening the auditory tube to allow air to flow between the pharynx and middle ear cavity

muscles of uvula

origin/insertion - lies within the uvula; action - shortens and broadens the uvula, to help close off the nasopharynx during swallowing