Muscles of the Face

• 1. Orbicularis oris superior/ orbicularis oris inferior

• 2. Muscles inserting into upper lip– Zygomatic minor– Levator labii superioris– Levator labii superioris alaeque nasi– Zygomatic major– Levator anguli oris

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Muscles of the Face

• 3. Muscles inserting into lower lip– Depressor anguli oris (also known as

triangularis)– Depressor labii inferior (also known as

quadratus labii inferior)–Mentalis

• 4. Transverse muscles– Rigorius– buccinator

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Muscles of the Face

– 1. Orbicular Oris • Superior (OOS) and

inferior (OOI)• Muscle that surround the

lips• Functional difference

between the upper and the lower muscles

• Pull the lips closer and effect labial seal

• OOS-lowers the upper lip• OOI- elevates the lower

lip• Also active when we

round and protrude lips.• Innervated by the VII

nerve

Muscles of the Face• Zygomatic minor

– Attaches to the zygomatic bone (ext.surface)

– Goes from zygomatic bone to the skin of the upper lip & OOS (mid-lateral region of the upper lip)

– When contracts, elevates upper lip

– In ‘p’- when releasing the ‘p’

– Innervated by the buccal branches of the VII facial nerve

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Muscles of the Face

• Levator labii superioris (LLS)– From lower margin

of orbit to the lateral half of the upper lip

– Inferior to skin & OOS

– Elevates the upper lip

– Innervated by the buccal branches of the VII facial nerve 5

Muscles of the Face

• Levator labii superior alaeque nasi (LLSAN)– From frontal process

of the maxilla & lower orbital regions

– Inserts into mid-lateral region of upper lip (OOS)

– Elevates the upper lip and dilating the nostril

– Innervated by the buccal branches of the VII facial nerve

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Muscles of the Face• Zygomatic major

– It arises lateral to the zygomatic minor on the zygomatic bone

– Inserting into the corner of the OOS.

– Elevates the lip & pulls the oral angle laterally

– (e.g., /i/; superior and lateral movement of upper lip)

– Buccal branches of the VII facial nerve

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Muscles of the Face• Levator anguli oris

(LAO) (also known as caninus)– Deep to the other lip

muscles– From the maxilla

around the lower orbit to the oral angle

– Draws the corner of mouth up and medially

– Buccal branches of VII facial nerve

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3. Muscles inserting into lower lip

• Depressor anguli oris (DAO) (also known as triangularis)

• Attached at the oblique line of the mandible to the skin & OOI at the oral angle

• Pulls oral angle down and laterally

• Lowering the lower lip inferiorly

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3. Muscles inserting into lower lip

• Depressor labii inferior (DLI) (also known as quadratus labii inferior)

• Also from oblique line of mandible into the lower lip and inserts into the skin & OOI (not to the angle)

• Lower the lower lip inferiorly

• Dilates orifice by pulling lip down and out

• Innervated by the mandibular marginal branch of the VII facial nerve

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3. Muscles inserting into lower lip

• Mentalis (MTL)• Closer to the midline• Medial pair of muscle.• From mandible up to

OOI• Elevates the lower lip

(same as OOI) for lip closure

• Wrinkles chin and pulls lower lip out

• Mandibular marginal branch of the VII facial nerve

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4. Transverse muscles

• Risorius (RIS)– From angle of

mandible to angle of the mouth.

– Movement of angle laterally

– Retracts lips at the corners

– Buccal branches of the VII facial nerve

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4. Transverse muscles

• Buccinator• Deep to risorius is the

buccinator• Muscular bulk of the

cheek• From the large areas of

mandible and maxilla to OOS and OOI at the angle

• Movement of food onto the grinding surfaces of the molars

• Also contributes to moving angle laterally and helps to flatten the cheeks

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5. Platysma

• Platysma (PLAT)• Very thin, flat , broad

muscle• Covers most of the

lateral and anterior regions of the neck

• Runs from region around pectoralis major inserting into the oral angles.

• Depresses the mandible• Active when smiling

broadly. Also active when resisting jaw against resistance

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Muscles of the Tongue

• Tongue is covered by –Mucous membrane superficially – Deep structures are formed by the

corium (layer of connective tissues), fibrous midline septum and deep connective tissues of the lingual mucosa

– In addition, there is an array of intrinsic muscles and attachments from extrinsic muscles

Muscles of the Tongue

• Extrinsic• Palatoglossus• Styloglossus• Hyoglossus• Genioglossus

• Intrinsic• Superior longitudinal• Transverse• Vertical• Inferior longitudinal

Intrinsic Tongue Muscles

• Superior longitudinal muscles: comprise the upper layer of the tongue, course forward and outward. Will elevate the tip of the tongue. CN. XII

• Inferior longitudinal muscles: Lower layer of the tongue and will pull the tongue downward. CN. XII

Intrinsic Tongue Muscles

• Transverse muscles: course laterally and insert to the sides of the tongue.Leads to pull the edges of the tongue together. CN. XII

• Vertical muscles: At right angles to the transverse muscles and help in flattening the muscles. CN. XII

Coronal Section of the Tongue

Extrinsic Tongue Muscles• Genioglossus:

– originates from the Inner mandibular surface and fans to the tip and dorsum of the tongue

– Contraction of the anterior fibers causes retraction

– contraction of the posterior fibers draws the tongue forward.

– Contraction of both fibers will lead draw the tongue down into the floor. CN. XII hypoglossal nerve

Muscles of the Tongue

Extrinsic Tongue Muscles

• Hyoglossus: greater horn of the hyoid to the sides of the tongue.Pulls the sides down. CN. XII

• Chondroglossus: Lesser horn of the hyoid, courses upward and inserts into the intrinsic muscles. Depresses the tongue. CN XII hypoglossal nerve

Extrinsic Tongue Muscles

• Styloglossus: – originates from the

anterolateral margin of the styloid process of the temporal bone

– courses forward and downward and inserts into the inferior surfaces of the tongue.

– Pulls it upward and backward.

– CN. XII hypoglossal nerve

Muscles of the Tongue

• Palatoglossus• May be defined as a

muscle of the tongue or the velum

• It serves dual purpose of depressing the soft palate or elevating the back of the tongue

• The palatoglossus makes up the anterior faucial pillar.

Palate

• Soft Palate: attached to the posterior free border of the palatine bones

• Muscles– Levator veli palatini muscle: CN X & XI.

Primary elevator–Muscularis uvulae: Shortens the soft

palate. CN X & XI– Tensor veli palatini muscle: tenses and

flattens the soft palate. Also opens the ET. CN V

Palate

• Muscles– Palatoglossus muscle: Forms the

anterior faucial pillars. Helps elevate the tongue or depresses the soft palate. CN. X & XI

– Paltopharyngeus muscle: Forms the posterior faucial pillars. Narrows the pharyngeal area and lowers the soft palate. CN. X & XI

Tongue Movement

• Which muscles are responsible for:– Tongue tip elevation– Tongue tip depression– Tongue tip deviation (left and right)– Relaxation of lateral margins– Tongue narrowing– Central tongue grooving– Tongue protrusion– Tongue retraction– Posterior tongue elevation– Tongue body depression

Tongue Movement

• Most important of the articulators as it is involved in production of the majority of English phonemes

• Tongue gestures required for speech– Tongue tip elevation• Superior longitudinal muscle of the tongue• Shortening of these fibers will pull the tip and

lateral margins up

• Tongue tip depression– Inferior longitudinal muscles– They course along the lateral margins of the

lower tongue making them well positioned for pulling the tip and sides down

• Tongue tip deviation– Simultaneous unilateral contraction of the

superior and inferior longitudinal muscles– Right side contraction will pull tongue to the

right and left side contraction will pull tongue to the left

Tongue Movement

• Relaxation of lateral margins– Important for /l/– Slight contraction of the posterior

genioglossus, which helps to move the tongue forward

– Also contraction of the transverse intrinsic muscle to pull the sides medially away from the lateral gum ridge

Tongue Movement

• Tongue narrowing– Fibers that course from the median

fibrous septum to the lateral margins of the tongue; the transverse intrinsic

• Central tongue grooving– For major grooving; contraction of the

entire genioglossus in conjunction with the vertical fibers

– For moderate grooving: the genioglossus to a lesser degree and the vertical muscles

– A broadened groove could be accomplished by co-contraction of the superior longitudinal muscle, as well

Tongue Movement

• Tongue protrusion– Posterior genioglossus and at least two

of the intrinsic muscles– Posterior genioglossus draws the tongue

forward, but won’t point it– Pointing will be done by the vertical and

transverse intrinsic muscles– Deviation (up, down, to the sides) will

require the use of superior and inferior longitudinal intrinsics

Tongue Movement

• Tongue retraction

– Co-contraction of the superior and inferior longitudinal muscles will shorten the tongue

– To retract the tongue into the pharyngeal space, the styloglossus will also be engaged

Tongue Movement

• Posterior tongue elevation– Palatoglossi will elevate the sides– Contraction of the transverse muscles in the

posterior tongue will assist in bunching the tongue up in that region

• Tongue body depression– Contraction of the genioglossus will depress

the medial tongue– Additionally, contraction of the hyoglossus and

chondroglossus will depress the sides of the tongue, if the hyoid is fixed by the infra hyoid muscles

Palate

• Soft Palate: attached to the posterior free border of the palatine bones

• Muscles– Levator veli palatini muscle: It is a muscle

that forms the bulk of the velum– Arises from the apex of the petrous portion

of the temporal bone & medial wall of the Eustachian tube and insert into the palatal aponeurosis of the soft palate

– CN X & XI. Primary elevator

Palate

– Tensor veli palatini muscle: – Does not tense the velum– It arises from the sphenoid bone

(scaphoid fossa) as well as from the lateral Eustachian tube wall.

– Its contraction dilates Eustachian tube– Innervated by the mandibular nerve of

the V trigeminal

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Palate

• Muscles– Palatoglossus muscle: Forms the

anterior faucial pillars. Helps elevate the tongue or depresses the soft palate. CN. X vagus & XI accessory

– Paltopharyngeus muscle: Forms the posterior faucial pillars. Narrows the pharyngeal area and lowers the soft palate. CN. X & XI

Biological Functions

• Mastication– Process involved in food preparation that

includes moving unchewed food, chewing it and mixing it with saliva

• Deglutition or Swallowing• These two functions require the

integration of lingual, velar, pharyngeal and facial muscles, with laryngeal movements

• About 55 muscles pairs that are integrated by the spinal and cranial nerves

Biological Functions

• Involves the following:–Muscular process inserting into the

orbicular oris so as close, open,purse, and retract the lips

– All the intrinsic muscles of the tongue that helps in moving the food for chewing and preparing the bolus for swallowing

– Velar elevators and tensors seal the nasal cavities

– Contraction of the pharyngeal constrictors to move the bolus down the pharynx and into the esophagus . Glosso infrengial cranial nerve 9.

Stages of Mastication and Deglutition

• Oral preparation Stage: – Food is introduced into the oral cavity, –Moved onto the molars for chewing, –Mixed with the saliva– Forming a concise bolus between the

tongue and the hard palate• Oral Stage:– The bolus is moved back by the

pressure of the tongue movement towards the hard palate

Stages of Mastication and Deglutition

• Pharyngeal Stage– Begins when the bolus reaches the

faucial pillars– Soft palate and the larynx elevate– Bolus is propelled through the pharynx to

the esophageal sphincter– Epiglottis is dropped to cover the

opening of the laryngeal opening– The intrinsic muscles adduct the VF– Food passes over the epiglottis into the

esophagus