ORAL CAVITY

LIPS

CHEEKS

TEETH

ALVEOLAR RIDGE

HARD PALATE

VELUM (SOFT PALATE)

BASIC INFORMATION ABOUT THE TONGUE

VELOPHARYNGEAL MECHANISM

MUSCLES OF FACIAL EXPRESSION

LIST OF CONTENTS

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In the process of speech production, the oral cavity is considered as the most active. There are various anatomical structures that make up the alveolar ridge: the tongue, velum, and mandible. The oral cavity includes the faucial pillars, tonsils, velopharyngeal (V-P) mechanism, and face muscles. These structures, excluding the facial muscles, together form the mouth. The mouth performs both primary (biologic) and secondary (nonbiologic) tasks. Biologically, the mouth connects the respiratory and digestive systems to the outside world. The mouth is employed in the digestive processes of mastication (chewing) and deglutition (swallowing). Food digestion starts in the mouth.

Primary function

· Biological

· Mouth serves as conduit

· Mouth is used for mastication and deglutition for digestion

Secondary function

· Non-biological or for speech

· Mouth is used for speech sound through resonance

LIPS

Lips (rima oris) are made up of four layers of tissue: cutaneous, muscular, glandular, and mucous. Fat may also be accumulated within these layers in varying proportions. Skin is the cutaneous layer. A layer of muscular tissue lies underneath the skin. The orbicularis oris is a sphincter muscle that surrounds the lips. The orbicularis oris has two layers. The deep layer contains concentric rings of muscle fibers, whereas the superficial layer gets fibers from other face muscles (these muscles will be discussed later). The glandular layer includes labial glands, which look like saliva glands. It is also connected to the oral and pharyngeal mucous membranes. The superior and inferior labial frenulae bind the lips to the alveolar area (upper lip) and mandible (lower lip) on their lingual surface (singular: frenulum).

The outer surface of the lips shows various landmarks. The lips appear darker than the rest of the face owing to the vermilion zone's transparency (this transparency is created by an abundance of eleidin in the epithelium). The vermilion zone's transparency highlights the vascular tissue underneath. Two vertical ridges with a deep furrow between them go from the septum of the nose to the center of the top lip. The philtrum is this ridge. The philtrum ends on the top lip, forming a midline dip that resembles an archer's bow. Cupid's bow refers to the upper lip's top border.

CHEEKS

The buccae, or cheeks, are connected to the lips by a ridge. The outermost layer is epidermis, followed by a mucous membrane, followed by muscle and glandular layers. The muscular layer of the cheeks contains many facial muscles that help in mastication and facial expression. The glandular layer contains five or six molar-shaped glands. The molar glands are appropriately named. The parotid salivary gland's Stenson's duct enters the buccal area. Finally, there may be a buccal fat pad. This pad is particularly visible in newborns, but it tends to fade as the child grows. The buccal cavity is formed by the cheeks, lips, gums, and posterior teeth.

TEETH

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TEETH

An adult's full set of teeth is 32, while a child's is just 20. Humans have two sets of teeth. The deciduous set is the first set that emerges in early life (but is also referred to by some people as the baby, milk, primary, or temporary teeth). Later, the permanent teeth replace the baby teeth. The permanent set has more teeth since the maxillae and mandible have grown larger.

There are four primary tooth types: incisors, cuspids (sometimes called canines), premolars, and molars. Food is sliced and sheared with ease using incisors. Cuspids resemble tusks. This configuration allows for tearing. They are flat with large surfaces, making them suitable for crushing and grinding.

The gross anatomy shows a crown, neck, and root. The crown is the visible component of the tooth (approximately one-third of the tooth). The undefined area between the crown and root is usually at the gum line. The crown is coated with enamel (96% mineral), whereas the root is covered in cementum (approximately 50 percent mineral by weight). The neck is the cementoenamel junction, where enamel meets cementum. Dentin is the majority of a tooth's solid part.

· External surface

Crown = can be seen, approximately ⅓ of tooth; Covered by enamel

Neck = generally gum lime

Cementoenamel joint

Root = lies below gum line, approximately ⅔ of tooth; Covered by

cementum

Dentin = bulk of the solid portion of a tooth

The tooth is anchored within dental alveolus by a periodontal ligament

· Gomphosis joint

· Internal view

Hollow = forms a pulp canal; Larger portion of pulp canals is referred as pulp cavity; § Filled with dental pulp
- - § Nerve fibers and blood vessels make their way into pulp cavity through the apical foramen (at the bottom of the tooth roots)

Depending on its type, a tooth can have any number of surfaces

· Contact surface

· Incisor = incisal edge

· Other teeth = occlusal surface

· Posterior surface (facing the oral cavity) - lingual surface

· Anterior surface

· Incisors and cuspids = labial surface

· Premolars and molars = buccal surface

· Adjacent teeth have approximal surfaces

§ Mesial and distal surfaces

ROOTS

· 1 = incisors, cuspids, bicuspids

o Upper first bicuspids amy have two roots

· 2 = lower molars

· 3 = upper molars

OCCLUSAL SURFACES

· Bicuspids and molars are flatter than incisors and cuspids

o Cusps

§ Bicuspids - 2

§ First molars - 4

§ Second molars - 3-4

§ Third molars - 3

1. First consonant sounds: 6-9 months

· Labial /p/. /m// or alveolar /t/, /d/, /n/

2. First primary teeth emerge between 6-10 months

3. 20 primary teeth are in place by ~30 months

4. Labiodental /f/ (~30-36 months), /v/ (48 months)

5. Linguodental /th/ sounds (~54-60 months)

TYPES OF OCCLUSION

· Normal occlusion

o Maxillary and mandibular arches are aligned with each

other when they are occlusion or with mouth closed

· Class I malocclusion

o Normal in terms of first molar but there’s misalignment in the anterior teeth (cuspids and bicuspids)

· Class II malocclusion

o Aka overbite

o Maxillary arch is more anterior because the molars are located more anteriorly

· Class III malocclusion

o Primary molar of maxillary dental arch is more posterior than mandibular dental arch

TEETH DEVELOPMENT

Tooth growth, calcification, eruption, and attrition occur in four phases. The tooth buds, enamel, and dentin develop throughout the growth period. During calcification, enamel and dentin solidify. The teeth are still lodged in the maxillae and mandible throughout these two phases. During the eruption stage, teeth begin to move into the oral cavity. Intraosseous and clinical substages exist. Intraosseous eruption occurs when teeth emerge from the alveolar ridge. The teeth are still not totally calcified, and the roots are still not fully developed. During resorption, osteoclasts tear down the bone tissue inside the alveolar ridge, causing the teeth to move. Osteoblasts rebuild the bone to make the alveoli once the teeth have erupted. The teeth cut through the gingivae to show clinical eruption. Attrition occurs throughout life. The mechanical forces of eating wear down the teeth. However, the teeth's spatial connections are preserved since eruption occurs continuously.

ALVEOLAR RIDGE

The alveolar ridge contains alveoli inside. It is a bony component of the mandible and maxilla. The maxillary ridge extends behind the upper and lower teeth. The bony ridge is mucous membrane covered. This mucous membrane connects to the oral cavity's mucous membrane. The maxillary alveolar ridge is clinically significant for speech-language pathologists because it produces various English consonant sounds.

HARD PALATE

The hard palate consists of the bone component of the oral and nasal ceilings. It is constructed from four bones and is not a single bone. The maxillae's palatine processes constitute the front three-quarters of the hard palate, whereas the palatine bones' horizontal processes form the posterior one-fourth. Right and left palatine and horizontal processes unite at the intermaxillary suture. The posterior nasal spine is generated when the two horizontal processes meet. The palatine processes are thicker anteriorly and laterally but thinner medially, creating a palatal arch. This arch varies greatly across individuals and is partially reliant on the maxillary dental arch.

· Formed by processes of four bones

o Anterior ¾: palatine processes of maxilla

o Posterior ¼: horizontal processes of palatine bones

§ Posterior nasal spine

§ Palatal arch

· Intermaxillary suture

· Covered by mucous membrane

· Rugae = transversely oriented; corrugation

· Midline raphe

· ⅕ of population may have torus palatinus

· Tissue surrounding it is likely to have bluish tint

VELAR MUSCLES:

VELUM (SOFT PALATE)

The soft palate is in the back. It moves and is made up of muscle fibers covered by a mucous membrane.

The palatal aponeurosis joins to the posterior free border of the palatine horizontal processes. This aponeurosis, together with other connective tissues, makes up around one-third of the velum's volume. There are various muscles in the intermediate layer. The superior pharyngeal constrictor muscles are continuous with the velum's muscular fibers laterally. Otherwise, the velar muscle is mostly in the middle. The velum's surface is a mucous membrane that connects to the mouth cavity.

Muscle: Levator veli palatini (levator palati)

Origin: Apex of petrous portion of temporal bone and medial wall of the Eustachian tube cartilage

Course: Down and forward

Insertion: Palatal aponeurosis of the soft palate, lateral to musculus uvulae

Innervation: Pharyngeal plexus from the XI accessory and X vagus nerves

Function: Elevates and retracts the posterior velum

Two muscles located at each side (right and left) that form a “v” shape. When it elevates, it pulls the velum superiorly.

Muscle: Musculus uvulae

Origin: Posterior nasal spines of the palatine bones and palatal aponeurosis

Course: Runs the length of the soft palate Insertion: Mucous membrane cover of the velum

Innervation: Pharyngeal plexus of XI accessory and X vagus nerves

Function: Shortens the soft palate

Muscle: Tensor veli palatini (tensor veli palati)

Origin: Scaphoid fossa of sphenoid, sphenoid spine, and lateral Eustachian tube wall

Course: Courses down, terminates in tendon that passes around pterygoid hamulus, then is directed medially

Insertion: Palatal aponeurosis

Innervation: Mandibular nerve of V trigeminal

Function: Dilates the Eustachian tube

Muscle: Palatoglossus (glossopalatine)

Origin: Anterior surface of the velum

Insertion: Lateral tongue

Action: It depresses the velum when the tongue is anchored. It also assists in triggering pharyngeal swallow reflex.

Muscle: Palatopharyngeus (pharyngopalatine)

Origin: Velum, pterygoid hamulis, and cartilage of the auditory tube

Insertion: Superior cornu of thyroid cartilage and lateral wall of the pharynx

Action:

It lowers the velum with more force than the palatoglossus. It pulls the velum backward and aids in guiding the bolus to the lower pharynx.

Muscle:

Superior pharyngeal constrictor

Origin: Medial pterygoid plate, pterygomandibular raphe, mylohyoid line, lateral tongue

Insertion: Medial pharyngeal raphe

Action: This aids the levator veli palatini in making the greater seal of the velopharyngeal port by pulling the posterior pharyngeal wall forward while pulling the lateral walls inward.

BASIC INFORMATION ABOUT THE TONGUE

TONGUE

Click the drop-down arrow on the side.

The tongue serves as the main sense of taste and helps with the processes of mastication and deglutition. Secondary to these other jobs is making speech sounds. The tongue is the main part of the body that changes the resonant characteristics of the vocal tract. It is also the main part of the body that makes many of the consonant sounds in English.

The tongue has two primary parts: blade and root. The blade is the part of the tongue that is easily seen. The root is below the blade and can't be seen very well. The tip, blade, front, and back are all parts of the blade. Putting the tongue against the ceiling of your mouth will make it rest against your front teeth, your alveolar ridge, your hard palate, and your velum. In the middle of the tongue, there's a groove called the longitudinal median sulcus. Two-thirds of the way down the dorsum of the tongue from its tip, a chevron-shaped landmark called the sulcus terminalis comes into play. It runs transversely and is perpendicular to the longitudinal median sulcus. At the point where the longitudinal median sulcus meets the sulcus terminalis, there is a small pit called the foramen cecum. This is where the foramen cecum is. At the back of the root of the tongue, three pieces of tissue come out and attach the base of the tongue to the epiglottis. These are the middle and the side glossoepiglottic folds. In between each of the lateral glossoepiglottic folds, there are small depressions called valleculae. These depressions are called valleculae because they are small. The surface of the tongue looks a little rough. Due to the fact that there are papillae on the surface of the tongue before the sulcus terminalis, this is why it looks like this. Papillae come in four types: filiform, fungiform, simple, and vallate; each one has a different shape. The taste buds live in the papillae, which are the parts of the body that make sense of taste.

THE TONGUE AS A MUSCULAR HYDROSTAT

· Means all muscles stiffen because of its musculature and flexible

· Intrinsic muscles

o Housed completely within tongue

· Extrinsic muscles

o Originate outside tongue

· Relatively little skeletal support, aside from hyoid and corium

· Tongue has ability to change its shape and position without diminishing its volume in the process

o Acts like a fluid-filled structure that is incompressible (muscular hydrostat)

§ Not really filled with fluid but muscle tissue

· Primary articulator, major structure responsible for modifying resonant characteristics of vocal tract

· 2 primary parts

o Blade (tip, blade, front, back)

§ Longitudinal median sulcus intersects with sulcus terminalis, where foramen cecum resides

· Root

§ Median and lateral glossoepiglottic folds

§ Between (M) and (L) are small depressions called valleculae

· Surface of tongue has rough appearance due to papillae (filiform, fungiform, simple, vallate)

· House taste buds

· (P) ⅓ is smoother in appearance than (A) portion

o Several mucous glands + lymphoid tissue (lingual tonsil)

· Anteriorly on undersurface of tongue

- lingual frenulum

· Outer surface of tongue - mucous membrane

· Inferior surface - thin mucous membrane

· Corium - basement layer of connective tissue of mucous membrane

o Dense, felt-like, “skeleton” of tongue

INTRINSIC TONGUE MUSCLES

There is a vertically oriented cavity inside the tongue called the fibrous midline septum that makes it possible for the muscles inside the tongue to be paired. Fibers from the superior longitudinal muscles can be found mostly in the middle of the tongue, while fibers from the inferior longitudinal muscles can be found more to the side. They both have fibers that run along the length of the tongue.

· Inferior longitudinal, superior longitudinal, transverse, vertical

· All paired, because of fibrous midline septum

o Independent neural innervation and blood supply

· Fibers of superior longitudinal muscles are confined primarily to mid-region, inferior longitudinals can be found more laterally

· Responsible for refined tongue movements and postures (elongating, flattening, narrowing, shortening)

Muscle: Inferior longitudinal

Origin: Root of the tongue and corpus hyoid

Course: Forward

Insertion: Tongue Apex

Innervation: XII Hypoglossal Nerve

Function: Pulls tip of the tongue downward, assists in retraction, and deviates the tongue

Muscle: Superior longitudinal

Origin: Submucous fibrous tissue of the tongue root and the median fibrous septum

Insertion: edges of the tongue and the fibrous membrane

Action: primarily works to elevate the tongue tip, but also assists in protruding and retracting the tongue, relaxing the lateral margins of the tongue, and moving the tip from side to side

Muscle: Transverse muscles of the tongue

Origin: Median fibrous septum

Insertion: Side of the tongue in the submucous tissue

Innervation: XII Hypoglossal Nerve

Action: Provide a mechanism for narrowing the tongue

Muscle: Vertical

Origin: mucous membrane of the dorsum of the tongue

Insertion: lateral and inferior surfaces of the tongue

Action: primarily works to flatten the tongue, but also assists in protruding the tongue and creating a longitudinal groove along the middle of the tongue

EXTRINSIC TONGUE MUSCLES

· responsible for gross positioning of the tongue

· Genioglossus, styloglossus, palatoglossus, hyoglossus

· Genioglossus

o Largest and strongest of all tongue muscles

· Styloglossus

o Antagonist of genioglossus

· Palatoglossus

o 3 functions (pulls velum down, elevates (P) position of tongue, does both)

Muscle: Genioglossus

Origin: Inner mandibular surface at the symphysis

Course: Fans up, back, and forward

Insertion: Tip and dorsum of tongue and corpus hyoid

Innervation: XII hypoglossal nerve

Function: Anterior fibers retract the tongue; posterior fibers protrude the tongue; together, anterior and posterior fibers depress the tongue

Muscle: Hyoglossus

Origin: Length of greater cornu and lateral body of hyoid

Course: Upward

Insertion: Sides of the tongue between styloglossus and inferior longitudinal muscles

Innervation: XII hypoglossal nerve

Function: Pulls sides of the tongue down

Muscle: Palatoglossus

Origin: Anterolateral palatal aponeurosis

Course: Down

Insertion: Sides of posterior tongue

Innervation: Pharyngeal plexus from the XI accessory and X vagus nerves

Function: Elevates the tongue or depresses the soft palate

Muscle: Styloglossus

Origin: Anterolateral margin of styloid process

Course: Forward and down

Insertion: Inferior sides of the tongue

Innervation: XII hypoglossal nerve

Function: Draws the tongue back and up

Source: https://commons.wikimedia.org/wiki/File:Rotation_mandible_bone.gif

MANDIBLE

The condylar process of the mandible articulates with the mandibular fossa of the temporal bone to produce the TMJ. The articular meniscus separates the mandibular condyle from the mandibular fossa. A fibrocartilage covers the condyle and mandibular fossa that actually articulate. Unlike other joints, most bones that articulate with each other are cushioned by hyaline cartilage. The main distinction between hyaline and fibrocartilage is the absence of vascular tissue. The TMJ would compress blood vessels if the articular surfaces were coated with hyaline cartilage. Finally, the articular capsule encapsulates the whole TMJ. Ligaments hold the condyle in place. The temporomandibular (lateral), sphenomandibular, and stylomandibular ligaments are examples.

· articulation of condylar process of mandible with the mandibular fossa of temporal bone

o Indirect articulation because of separation by articular meniscus

o Surfaces are covered by fibrocartilage (devoid of vascular tissue)

· Entire TMJ is encapsulated by articular capsule

· Condyle held in place by temporomandibular, sphenomandibular, stylomandibular ligaments

· Ginglymoarthrodial joint

· Vertical, anteroposterior, and transverse dimensions of movement

MANDIBULAR MOVEMENTS

· Protrusion

o Simultaneous contraction of (M and L) pterygoid muscles

· Retraction

o Simultaneous contraction of

(P) fibers of temporalis and

(A) belly of digastricus as well as the mylohyoid and geniohyoid muscles

· Lateralization

o simultaneous contraction of lateral pterygoid and (P) portion of temporalis

MANDIBULAR ELEVATORS

Elevation (closed)

· Masseter

o Most powerful muscle of mastication, slow, has both internal and external fibers

· medial/internal pterygoid

o Plus masseter = mandibular sling

· Temporalis

o Quicker, snapping action

Muscle: Masseter (external body)

Origin: anterior position o the zygomatic arch

Insertion: angle and lateral surface of the mandibular ramus

Action: along with the medial (internal) pterygoid straps the mandible to the skull; primarily closes and retracts the jaw;

Muscle: masseter (internal body)

Origin: posterior and medial portion of the zygomatic arch

Insertion: upper half of the ramus and lateral surface of coronoid process of the mandible

Muscle: medial (internal) pterygoid

Origin: pterygoid fossa and medial surface of lateral pterygoid plate

Insertion: inner surface of the ramus and angle of the mandible

Action: along with the masseter, straps the mandible to the skull; primarily elevates the mandible; assists in the protruding the mandible

Muscle: temporalis

Origin: entire temporal fossa

Insertion: anterior border of the ramus and coronoid process of the mandible

Action: primarily elevates the mandible; assists in retracting the mandible and moving the mandible laterally

MANDIBULAR DEPRESSORS

Depression (open)

· Digastricus

· Mylohyoid

· Geniohyoid

· Lateral/External pterygoid

Muscle: Digastricus anterior

Origin: Inner surface of the mandible at digastricus fossa, near the symphysis

Course: Medially and down

Insertion: Intermediate tendon to juncture of hyoid corpus and greater cornu

Innervation: Mandibular branch of V trigeminal nerve via the mylohyoid branch of the inferior alveolar nerve

Function: Pulls the hyoid forward; depresses the mandible if in conjunction with digastricus posterior

Muscle: Digastricus posterior

Origin: Mastoid process of temporal bone

Course: Medially and down

Insertion: Intermediate tendon to juncture of hyoid corpus and greater cornu

Innervation: Digastric branch of the VII facial nerve

Function: Pulls the hyoid back; depresses mandible if in conjunction with anterior digastricus

Muscle: Lateral (external) pterygoid

Origin: lateral greater wing of sphenoid and lateral pterygoid plate

Insertion: pterygoid fossa on the anterior neck of mandibular condyle

Action: primarily depresses the mandible; bilateral contraction assists in protruding mandible; unilateral contraction will assist in lateral mandibular movement (i.e., a grinding action)

Muscle: Geniohyoid

Origin: Mental spines of the mandible

Course: Medially

Insertion: Corpus hyoid

Innervation: XII hypoglossal nerve

Function: Depresses the mandible

Muscle: Mylohyoid

Origin: Mylohyoid line, inner mandible

Course: Back and down

Insertion: Median fibrous raphe and inferiorly to hyoid

Innervation: Alveolar nerve, arising from the V trigeminal nerve, mandibular branch

Function: Depresses the mandible

FAUCIAL PILLARS

The faucial pillars are visible when you open your mouth and look in a mirror. The uvula, a single bulb-like structure at the end of the velum, is a point of reference. Two folds of skin may be seen on each side of the uvula if you follow it down the rear of the mouth cavity. The faucial pillars are these folds. These folds have muscle fibers hidden beneath the mucosal membrane. The anterior faucial pillars include palatoglossus fibers. The palatopharyngeus fibers are in the posterior pillars. The front pillars are called palatoglossal folds, whereas the posterior pillars are called palatopharyngeal folds. Between these two folds lies the tonsillar fossa.

· Anterior and posterior faucial pillars

· Within them are muscle fibers

o anterior/palatoglossal folds = palatoglossus muscle fibers

o posterior/palatopharyngeal folds = palatopharyngeus muscle fibers

· Tonsillar fossa = space existing between these two folds

TONSILS

Tonsils are organized in a circle, thus the name Waldeyer's ring. The lingual tonsil was addressed in the tongue section. The floor of Waldeyer's ring is this tonsil near the posterior tongue's base. The palatine tonsils form the ring's lateral walls. The tonsillar fossae are located between the anterior and posterior faucial pillars. Some tonsillar fossae are still superior to the palatine tonsils. The supratonsillar fossa. The pharyngeal tonsil, or adenoids, constitute the ring's roof. The adenoids line the posterior pharyngeal wall at the velum.

Tonsils are lymphoid tissues that combat infection. As microorganisms enter the oral and pharyngeal cavities, the tonsils trap them to keep the upper respiratory tract healthy. Tonsils may become inflamed and infected. Pus accumulates in the supratonsillar fossae. Because the Eustachian tube's pharyngeal ostium (opening) lies near the adenoids, any infection of the adenoids may reflux into the tube and reach the middle ear cavity.

· Lingual tonsil

o At base of posterior tongue, floor Waldeyer’s ring

· Palatine tonsils

o Lateral walls of Waldeyer’s ring

o Housed within tonsillar fossae of (A and P) faucial pillars

§ Aka Supratonsillar fossa

VELOPHARYNGEAL MECHANISM

Responsible for regulating communication between oral and nasal cavities.
Digestive and speech functions
Velum + posterior pharyngeal wall

a. Closed: velum is raised to approximate PPW

b. Open: velum and PPW are separated

Passavant’s pad

a. Bulging of PPW and is present in some individuals.

V-P Closure

Activation of levator veli palatini - bilateral contraction > lift velum toward PPW in an angular fasion.
Musculus uvulae assis in elevating velum when a tighter seal is required (shortens velum, elevates velum, increases thickness of velum throughout a portion of its length)
Superior constrictor muscle contraction pulls PPW forward as it pulls lateral walls inward.
Friction generated by velum sliding up and down PPW causes velar glands to secrete lubricating substance to reduce friction.

V-P Opening

Velum is lowered by contraction of palatopharyngeus, palatoglossus, and to some extent - tensor veli palatini.

a. Palatopharyngeus acts as sling oriented in the opposite direction of levator velar palatini.

b. With pharyngeal attachment stabilized: vertical fibers of palatopharyngeus pull down and back on velum

c. With tongue stabilized: palatoglossus will also depress velum but with less force than palatopharyngeus during contraction.

d. TVP: minor role (lowers velum slightly, flattens velum, applies tension to palatal aponeurosis)

Other V-P mechanism

Assist in swallowing: activated during swallow and spindles from palatoglossus house special receptors for pharyngeal swallow reflex.
Phonation: as VFs vibrate, velum increases its height > greater supraglottic volume > drop in supraglottic pressure so that it remains less than subglottic pressure.

PURPOSE

· Humans communicate primarily through acoustic signal (speech), and also through facial expression

· Blinking, winking eyes, raising and lowering eyelids, pursing lips, frowning, smiling

MUSCLES OF FACIAL EXPRESSION

PLATYSMA

· Most superficial in the neck

LEVATOR LABII SUPERIORIS, ZYGOMATICUS MAJOR AND MINOR, AND LEVATOR LABII SUPERIORIS ALAEQUE NASI

· Elevate the lips and cupid’s bow

DEPRESSOR LABII INFERIORIS, DEPRESSOR ANGULI ORIS, AND MENTALIS MUSCLE

· Depress the lips

RISORIUS AND BUCCINATOR

· Retract the corners of the mouth

ORBICULARIS ORIS

· Most interior part of the lips

CORRUGATOR

· Corrugates your eyebrows towards the midline

EPICRANIUS FRONTALIS

· Scrunches up the forehead

Muscle: Orbicularis oris inferior and superior

Origin: Corner of lips

Course: Laterally within lips

Insertion: Opposite corner of lips

Innervation: VII facial nerve

Function: Constrict oral opening

Muscle: Risorius

Origin: Posterior region of the face along the fascia of the masseter

Course: Forward

Insertion: Orbicularis oris at the corners of mouth

Innervation: Buccal branch of the VII facial nerve

Function: Retracts lips at the corners

Muscle: Buccinator

Origin: Pterygomandibular ligament

Course: Forward

Insertion: Orbicularis oris at the corners of mouth

Innervation: Buccal branch of the VII facial nerve

Function: Moves food onto the grinding surfaces of the molars; constricts oropharynx

Muscle: Levator labii superioris

Origin: Infraorbital margin of the maxilla Course: Down and in to the upper lip

Insertion: Mid-lateral region of the upper lip

Innervation: Buccal branches of the VII facial nerve

Function: Elevates the upper lip

Muscle: Zygomatic minor

Origin: Facial surface of the zygomatic bone

Course: Downward

Insertion: Mid-lateral region of upper lip

Innervation: Buccal branches of the VII facial nerve

Function: Elevates the upper lip

Muscle: Levator labii alaeque nasi superioris

Origin: Frontal process of maxilla

Course: Vertically along the lateral margin of the nose

Insertion: Mid-lateral region of the upper lip

Innervation: Buccal branches of the VII facial nerve

Function: Elevates the upper lip

Muscle: Levator anguli oris

Origin: Canine fossa of maxilla

Course: Down

Insertion: Corners of upper and lower lips

Innervation: Superior buccal branches of VII facial nerve

Function: Draws corner of mouth up and medially

Muscle: Zygomatic major (zygomaticus)

Origin: Lateral to the zygomatic minor on zygomatic bone

Course: Obliquely down

Insertion: Corner of the orbicularis oris

Innervation: Buccal branches of the VII facial nerve

Function: Elevates and retracts the angle of mouth

Muscle: Depressor labii inferioris

Origin: Mandible at the oblique line

Course: Up and in to the lower lip

Insertion: Lower lip

Innervation: Mandibular marginal branch of the VII facial nerve

Function: Dilates orifice by pulling the lips down and out

Muscle: Depressor anguli oris (triangularis)

Origin: Lateral margins of the mandible on the oblique line

Course: Fanlike upward

Insertion: Orbicularis oris and upper lip corner

Innervation: Mandibular branch of the VII facial nerve

Function: Depresses corners of mouth and helps compress the upper lip against the lower lip

Muscle: Mentalis

Origin: Region of the incisive fossa of mandible

Course: Down

Insertion: Skin of the chin below

Innervation: Mandibular marginal branch of the VII facial nerve

Function: Elevates and wrinkles chin and pulls the lower lip out

Muscle: Platysma

Origin: Fascia overlaying pectoralis major and deltoid

Course: Up

Insertion: Corner of the mouth, region below symphysis mente, lower margin of mandible, and skin near masseter

Innervation: Cervical branch of the VII facial nerve

Function: Depresses the mandible

IMAGE SOURCES:

https://www.anatomynote.com/human-anatomy/head-skull-neck-anatomy/human-lips-anatomy-external-view/

https://giphy.com/explore/chubby-cheeks

https://www.medicinenet.com/image-collection/teeth_picture/picture.htm

https://bininj-kunwok.cdu.edu.au/glossary/alveolar-ridge/

https://teachmeanatomy.info/head/other/palate/

https://www.cancer.gov/publications/dictionaries/cancer-terms/def/hard-palate

https://brainly.in/question/10247013

https://www.kenhub.com/en/library/anatomy/levator-veli-palatini-muscle

https://quizlet.com/182570028/musculature-of-the-vp-mechanism-flash-cards/

https://www.kenhub.com/en/library/anatomy/tensor-veli-palatini-muscle

https://www.kenhub.com/en/library/anatomy/palatopharyngeus-muscle

https://www.daniellopezdo.com/swallowing-incorrectly-can-affect-eyes/palatoglossus-muscle/

https://www.kenhub.com/en/library/anatomy/superior-pharyngeal-constrictor

https://3d4medical.com/blog/intrinsic-and-extrinsic-muscles-of-the-tongue

https://www.researchgate.net/figure/Intrinsic-tongue-muscles-and-genioglossus_fig2_221928040

https://www.ncbi.nlm.nih.gov/books/NBK545141/figure/article-22195.image.f1/

https://teachmeanatomy.info/head/muscles/tongue/

https://mobilephysiotherapyclinic.net/styloglossus-muscle/

https://texasbeyondhistory.net/belle/images/belle-mandible.html

https://www.kenhub.com/en/library/anatomy/masseter-muscle

https://www.getbodysmart.com/mastication-muscles/medial-pterygoid-muscle

https://www.kenhub.com/en/library/anatomy/geniohyoid-muscle

https://anatomy.app/encyclopedia/digastric/

https://www.kenhub.com/en/library/anatomy/mylohyoid-muscle

https://www.healthline.com/health/swollen-tonsils

https://teachmeanatomy.info/neck/misc/tonsils-and-adenoids/

https://teachmeanatomy.info/head/muscles/facial-expression/

https://www.rehabmypatient.com/face/orbicularis-oris

https://www.rehabmypatient.com/face/risorius

https://www.rehabmypatient.com/face/buccinator

https://www.rehabmypatient.com/face/levator-labii-superioris

https://www.rehabmypatient.com/face/depressor-labii-inferioris

https://www.kenhub.com/en/library/anatomy/depressor-anguli-oris-muscle

https://www.rehabmypatient.com/face/mentalis

https://www.rehabmypatient.com/neck/platysma

REFERENCES:

Fuller, D. R., Pimentel, J. T., & Peregoy, B. M. (2012). Applied anatomy & physiology for speech-language pathology & audiology. Wolters Kluwer/Lippincott Williams & Wilkins Health.

Seikel, J. A., Drumright, D. G., & Seikel, P. (2013). Essentials of anatomy & physiology for communication disorders. Delmar Cengage Learning.

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