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Dr. Nabil Khouri MD, PhD
ORAL CAVITY II
THE TONGUE
Mass of striated muscles
covered with the mucous
membrane
 Divided into right and left
halves by a median septum
 Three parts:
 Oral (anterior ⅔)
 Pharyngeal (posterior
⅓)
 Root (base)
 Two surfaces:
 Dorsal
 Ventral

FUNCTIONS



The tonge is the most important
articulator for speech production.
During speech, the tongue can
make amazing range of
movements
The primary function of the
tongue is to provide a mechanism
for taste. Taste buds are located on
different areas of the tongue, but
are generally found around the
edges.
They are sensitive to
four main tastes: Bitter, Sour,
Salty & Sweet
DORSAL SURFACE
Divided into anterior two third and posterior one third by a Vshaped sulcus terminalis.
 The apex of the sulcus faces backward and is marked by a pit
called the foramen cecum
 Foramen cecum, an embryological remnant, marks the site of the
upper end of the thyroglossal duct
 Anterior two third: mucosa is rough, shows three types of
papillae:
 Filliform
 Fungiform
 Vallate
 Posterior one third: No papillae but shows nodular surface
because of underlying lymphatic nodules, the lingual tonsils

PAPILLAE
 CIRCUMVALLATE
PAPILLAE are arranged
in a row parallel to and in
front of sulcus terminalis
 FUNGIFORM PAPILLAE
are numerous at the tip
and margin of the tongue.
 FILLIFORM PAPILLAE
are prevalent on the
dorsum of the tongue
arranged in rows parallel to
sulcus terminalis
VENTRAL SURFACE
Smooth (no papillae)
 In the midline anteriorly,
a mucosal fold, frenulum
connects the tongue with
the floor of the mouth
 Lateral to frenulum, deep
lingual vein can be seen
through the mucosa
 Lateral to lingual vein, a
fold of mucosa forms the
plica fimbriata

MUSCLES

The tongue is composed of two types of muscles:
 Intrinsic
 Extrinsic

The intrinsic M
Confined to tongue
No bony attachment
Consist of:
▫ Longitudinal fibers
▫ Transverse fibers
▫ Vertical fibers
• Function: Alter the shape of
the tongue
INTRINSIC MUSCLES
MMUSCLE
USCLES OF THE TONGUE
FUNCTION
SUPERIOR
Shortens
tongue; curls
apex and sides
of tongue
INFERIOR
Shortens
tongue; uncurls
apex and turns
it downward
TRANSVERSE
Narrows and
elongates
tongue
VERTICAL
Flattens and
widens tongue
All intrinsic muscles are
supplied by Hypoglossal nerve
Intrinsic muscles
muscle
Origion and insertion
Action
Transverse
muscle
From the median septum and pass Narrow and
lateraly to be inserted into the side elongate the
of the tongue.
tongue.
Superior
Longitiudinal
muscle
Attached to the mucus membrane
over the posterior part of the
tongue and run forward to
attaches to the mucus membrane
at its edges and tip.
Shorting the
tongue and turn its
tip and edges
upwards.
Inferior
longitudinal
fibers
Situated lateral to genioglossus in
the lower part of the tongue.
Shorten the tongue
turn its tip and
edges downwards.
Vertical fibers
Run from the dorsum of the
tongue to the mucus membrane
on its ventral surface.
Flatten and
broaden the
tongue.
EXTRINSIC MUSCLES
Connect the tongue to the
surrounding structures: the soft
palate and the bones (mandible,
hyoid bone, styloid process)
 Include:

Palatoglossus
 Genioglossus
 Hyoglossus
 Styloglossus


Function: Help in movements of
the tongue
Extrinsic muscles
muscle
Origion and insertion
Action
Genioglossus
From the upper mental spine of the
mandible, its fiber run posteriorly
upward and downward.
Aprotracture and
depressor.
Hyoglossus
From the superior border of the
greater horn of the hyoid bone and
passes vertically upward.
Depress the tongue.
Styloglossus
From the anterior surface of the
styloid processes run forward
downward to enter the tongue below
the insertion of the palatoglossus
muscle.
Retractor of the
tongue.
palatoglossus
From the aponeurosis of the soft
palate and descends to the tongue.
Raise the tongue to
narrow the
oropharyngeal isthmus.
Condroglossus
From the lesser cornu of the hyoid
and ascending to blend with the
intrinsic lingual muscle.
MOVEMENTS
Protrusion:
 Genioglossus on both sides acting together
 Retraction:
 Styloglossus and hyoglossus on both sides
acting together
 Depression:
 Hyoglossus and genioglossus on both sides
acting together
 Elevation:
 Styloglossus and palatoglossus on both sides
acting together

SENSORY NERVE SUPPLY
Anterior ⅔:
 General sensations:
Lingual nerve
 Special sensations :
chorda tympani
 Posterior ⅓:
 General & special
sensations:
glossopharyngeal nerve
 Base:
 General & special
sensations: internal
laryngeal nerve

MOTOR NERVE SUPPLY

Intrinsic muscles:


Extrinsic muscles:


Hypoglossal nerve
All supplied by the
hypoglossal nerve,
except the
palatoglossus
The palatoglossus
supplied by the
pharyngeal plexus
BLOOD SUPPLY
Arteries:
 Lingual artery
 Tonsillar branch of
facial artery
 Ascending
pharyngeal artery
 Veins:
 Lingual vein,
ultimately drains into
the internal jugular
vein

Lingual
artery & vein
Hypoglossal
nerve
Dorsal lingual
artery & vein
Deep lingual
vein
LYMPHATIC DRAINAGE



Tip:
 Submental nodes
bilaterally & then deep
cervical nodes
Anterior two third:
 Submandibular
unilaterally & then
deep cervical nodes
Posterior third:
 Deep cervical nodes
(jugulodigastric
mainly)
SPECIALIZED MUCOSA
•
•
•
•
Covers the dorsum of the tongue.
Occupies 15% of the oral cavity.
Although it is masticatory mucosa by function but due to its high
extensibility and lingual papillae, it is classified as
“SPECIALIZED MUCOSA”.
Lingual Papillae:
These are the small nipple or hair–like structures on the upper surface of the
tongue that give the tongue its characteristic rough texture.
Four types of papillae are found on dorsum of the tongue:
1. Fungiform papillae
2. Filiform papillae
3. Foliate papillae
4. Circumvallate papillae

•
Fungiform
Papillae:
fungus-like appearance
present on tip and sides of
tongue
scattered between filiform
papillae
smooth, rounded structures
covered by non-keratinized
epithelium
Appear red due to highly
vascular CT
Taste buds are present on the
superior surface
Dr.Syed Sadatullah
King Khalid University
Fungiform Papillae
•
Filiform Papillae
Hair-like appearance
Cover entire anterior part of
tongue
Cone-shaped structures
covered by thick keratinized
epithelium
Form a tough surface
involved in compressing and
breaking food when tongue is
apposed to hard palate
Dr.Syed Sadatullah
King Khalid University
Filliform Papillae
•
Foliate Papillae
Leaf-like appearance
Present on lateral margins of posterior part of tongue
Consist of parallel ridges that alternate with deep grooves in the mucosa
A few taste buds are present in their lateral walls
 Circumvallate papillae
 Arranged anterior to sulcus terminalis 8-12
in number
 Large structures surrounded by a deep, circular groove into which
ducts of minor salivary glands (Glands of Ebner) open
 Covered by keratinized epithelium on superior surface and nonkeratinized epithelium on lateral surface
Dr.Syed Sadatullah
King Khalid University
Circumvallate Papilla and Taste buds (arrows)
TASTE BUDS
GINGIVA
Consists of dense vascular fibrous tissue which is covered by
mucuos membrane and attached to the alveolar margins of the
jaws.
http://pocketdentistry.com/9-oral-mucosa-and-mucosal-sensation

Dorsal tongue. (a) The dorsal surface of the tongue is
covered by specialized mucosa. The roughness of the surface is
attributable to the abundant, small hair-like filiform papillae
that cover much of the anterior two- thirds of the tongue, and
lack taste buds. The less numerous, small, round, white-red,
papular fungiform papillae are distributed over the dorsal
surface (center of grey circles). On the most posterior one
third of the oral portion of the tongue are the 8 to 12 large
circumvallate papillae (arrows) that are lined up in a Vformation and converge at the foramen cecum. (b) This view of
the dorsal tongue demonstrates the arrangement of
circumvallate papillae in a V-shaped configuration at the
junction of the anterior two-thirds and the posterior one-third
(arrows). (c) Taste buds (arrows) are present in the epithelium
of the lateral surfaces of the circumvallate papilla. (d) An
individual taste bud within the epithelium of the papillary
trough. The orifice (taste pore) (arrow) of the taste bud opens
into the lateral wall of the circumvallate papilla, allowing for
taste sensation to be received by the taste bud.
SOFT PALATE
Attached to the posterior border of the hard palate
 Covered on its upper and lower surfaces by mucous
membrane (Palatine Aponeurosis)
 Composed of:
 Muscle fibers
 An aponeurosis
 Lymphoid tissue
 Glands
 Blood vessels
 Nerves

PALATINE APONEUROSIS





Fibrous sheath
Attached to posterior border of hard palate
Is expanded tendon of tensor velli palatini
Splits to enclose musculus uvulae
Gives origin & insertion to palatine muscles
1.
Uvula is the median conical projection
marked by median raphe.
2.
Palatine arches are free margins of the
soft palate and splitting into two parts
as they approach the lateral wall.
a. Palatoglossal arch or anterior
pillar of fauces or anterior palatine
arch encloses the palatoglossus
muscle.
b. Palatapharyngeal arch or
posterior pillar of fauces or posterior
palatine arch encloses the
palatopharyngeus muscle.
MUSCLES

Tensor veli palatini




Levator veli palatini




Origin: spine of sphenoid;
auditory tube
Insertion: forms palatine
aponeurosis
Action: Tenses soft palate
Origin:petrous temporal bone,
auditory tube, palatine
aponeurosis
Insertion: palatine aponeurosis
Action: Raises soft palate
Musculus uvulae



Origin: posterior border of hard
palate
Insertion: mucosa of uvula
Action: Elevates uvula
MUSCLES

Palatoglossus
Origin: oral surface of
palatine aponeurosis
Insertion: side of tongue at
the junction of oral and
pharyngeal parts
Action: pulls root of tongue
upward, closes
oropharyngeal isthmus
 Palatopharyngeus
Origin: Ant Fasciculus-Post border of hard palate Post fasciculus-palatine aponeurosis
Insertion: posterior border of thyroid cartilage,
wall of the pharynx and its median raphe.
Action: Elevates wall of the pharynx
Non-Ketratinized stratified epith.
SENSORY NERVE SUPPLY


Mostly by the maxillary nerve through its branches:
 Greater palatine nerve
 Lesser palatine nerve
 Nasopalatine nerve
Glossopharyngeal nerve supplies the region of the soft palate
MOTOR NERVE SUPPLY

All the muscles, except tensor veli palatini, are
supplied by the:


Pharyngeal plexus
Tensor veli palatini supplied by the:

Nerve to medial pterygoid, a branch of
the mandibular division of the
trigeminal nerve
BLOOD SUPPLY



Branches of the
maxillary artery
 Greater palatine
 Lesser palatine
 Sphenopalatine
Ascending palatine,
branch of the facial
artery
Ascending pharyngeal,
branch of the external
carotid artery