The document provides detailed information about the anatomy of the mouth, including the tongue, palate, salivary glands, and taste sensation. It describes the tongue's structure, muscles, blood and lymph supply. The dorsal surface of the tongue contains various papillae that provide texture and contain taste buds. The document outlines the three pairs of major salivary glands - parotid, submandibular, and sublingual glands - and their locations, ducts and blood supply. Taste buds are located on papillae on the tongue and contain receptor cells that detect the five basic tastes: sweet, salty, sour, bitter and umami.

1. DR :MohanadRahmanAlwan
ANATOMYOF THE MOUTH (2)
QAP 20704

2. THE TONGUE
 The tongue is a muscular organ
in the mouth.
 It forms part of the floor of the
oral cavity and part of the
anterior wall of the oropharynx.
 The apex of tongue is anterior
part in oral cavity and directly
sits behind the incisor teeth
 The root of tongue is attached
to the mandible and the hyoid
bone.

3. THE TONGUE
• It is covered with moist, pink tissue
called mucosa.
• Tiny bumps called papillae give
the tongue its rough texture.
• Thousands of taste buds cover the
surfaces of the papillae.
• Taste buds are collections of
nerve-like cells that connect to
nerves running into the brain.

4. THE TONGUE
 Its ventral surface is
covered by non-
keratinized stratified
squamous epithelium and
the dorsal surface is
covered by various
papillae.

5. DORSAL SURFACE OF TONGUE
Posterior 1/3 (pharyngeal Part) residing in the
oropharynx
Anterior 2/3 (Oral Part) residing in the oral cavity
Sulcus terminalis – groove
separates the tongue into two areas:
The dorsal surface of the tongue is divided into
an anterior 2/3 or oral part and a posterior 1/3
or pharyngeal part by a prominent sulcus
terminalis

7. DORSAL SURFACE OF TONGUE (ORAL PART)
 The oral part of the tongue has a velvety appearance, since
its mucous membrane is covered by small projections called
Papillae.
 Most of papillae are pointed filiform papillae: look like
“hooks” that are composed of hard keratinized epithelium.
 The fungiform papillae: Mushroom-shaped and slightly
higher than surrounding filiform papillae. To the naked eye,
they appear as red spots on the tongue, containing taste buds
at their base.
 The circumvallate papillae are much larger than fungiform
papillae, with numerous taste buds.

8. DORSAL SURFACE OF TONGUE (ORAL PART)

9. DORSAL SURFACE OF TONGUE (PHARYNGEAL
PART)
 The pharyngeal surface of the tongue lies just behind a row
of very large vallate papillae which form the sulcus
terminalis .
 The mucosa covering the pharyngeal surface of tongue is
irregular contour because of the many small nodules of
lymphoid tissue in the submucosa.
 These nodules are collectively the lingual tonsil

10. DORSAL SURFACE OF TONGUE

11. DORSAL SURFACE OF TONGUE

12. MUSCLES OF THE TONGUE
 The muscles of the tongue
can be divided into:
I. Extrinsic muscles
II. Intrinsic muscles (allow
for shape change with fibers
in various directions)
(superior longitudinal,
inferior longitudinal
,transverse and vertical
muscles)

13. EXTRINSIC MUSCLES OF TONGUE
• There are four major extrinsic
tongue muscles:
• Hyoglossus
• Styloglossus
• Genioglossus
• Palatoglossus

14. MUSCLES OF THE TONGUE
 Extrinsic muscles serve to
move the tongue about in
the oral cavity.
 Intrinsic muscles act to
change the shape of the
tongue.

15. EXTRINSIC MUSCLES
Muscle Origin Insertion Innervation Function
Genioglossus
Superiormental
tubercles
Body of hyoid;
entire lengthof
tongue
Hypoglossalnerve
[XII]
Protrudes tongue;
depresses center of
tongue
Hyoglossus Greater horn and
adjacent part of
body of hyoid bone
Lateral surfaceof
tongue
Hypoglossalnerve
[XII]
Depresses tongue
Styloglossus Styloid process
(anterolateral
surface)
Lateral surfaceof
tongue
Hypoglossalnerve
[XII]
Elevates and
retracts tongue
Palatoglossus
Inferior surfaceof
palatine
aponeurosis
Lateral margin of
tongue
Vagus nerve [X]
(via pharyngeal
branch to
pharyngealplexus)
Depressespalate;
moves
palatoglossal fold
toward midline;
elevates back of
the tongue

16. BLOOD SUPPLY OF TONGUE
 Arterial blood supply :
 The main artery is the
which a
external
lingual artery
branch of the
carotid artery.
 Venous drainage
 Dorsal lingual and deep
lingual veins.

17. LYMPHATIC OF THE TONGUE
1. Tip of tongue to
submental LN group.
2. Rest of anterior 2/3 of tongue
to submandibular LN
group and deep cervical LN
group
3. Posrerior 1/3 of tongue to
deep cervical LN group

18. SENSORY INNERVATIONS
 Theanterior 2/3ofthetongue is
carriedby :
1. Thelingualnerve,amajor branchofthemandibularnerve
(abranchofthetrigeminal nerve,(CNV)forgeneral
sensation.
2. Thechordatympani(abranch ofthefacialnerve(CNVII)
that runsin thelingualnerve)for taste.

19. SENSORY INNERVATIONS
 Theposterior1/3ofthe tongueandthevallate papillaeare
suppliedbythe glossopharyngealnerve (CNIX)forboth
general sensation and taste.
 Vagus Nerve (CN X)– Taste of Posterior Part
 Motor innervations
 Muscles of the tongue are innervated by the
hypoglossal nerve (the twelfth cranial nerve,
(CN XII)

21. SENSATION OF
TASTE
• Structure of Taste Buds Each
Taste Bud is a bundle of
receptor cells.
• It contains about 40 cells
which are the modified
epithelial cells
• Cells are divided into 4
groups 1) Type 1 cells 2) Type
2 cells 3) Type 3 cells 4) Type
4 cells

22. TYPES OF TASTE
Sweet Taste- Produced by Organic Substances like
Monosaccharides, Polysaccharides, Glycerol, Aldehydes,
Ketones.
 Salt Taste- Produced by Chlorides and Nitrates of Na, K &
Ammonia.
 Sour Taste- Produced because of Hydrogen ions. •
Bitter Taste- Produced due to organic substances like
Strychnine, Morphine, Piric Acid, Bile Salts, Salts of Ca, Mg &
Ammonium. •
Umami- Produced due to Glutamate, particularly Monosodium
Glutamate.

24. PALATE
 Palate is a roof of the
mouth; the partition
separating the nasal and
oral cavities.
 consisting of an anterior
bony portion (hard
palate) and a posterior
muscular portion (soft
palate)

25. PALATE
• Hard Palate (anterior
2/3)
• Bones: Maxilla (Palatine
processes + Palatine
Bone)
• Assists the tongue in
chewing

26. PALATE
 Soft palate (posterior 1/3)
 Mobile fold formed mostly of
skeletal muscle
 Closes off the nasopharynx
during swallowing
 Uvula projects downward from
its free edge

27. SALIVARY GLANDS
 The salivary glands are
exocrine glands, glands
with ducts, that produce
saliva.
 They secrete amylase, an
enzyme that breaks down
starch into maltose.

28. SALIVARY GLANDS
 Three pairs of extrinsic glands:
parotid, submandibular, and
sublingual.
 Intrinsic salivary glands
scattered throughout the oral
mucosa (Nose, lip, buccal
mucosa, palate, pharynx).
 > 400 minor salivary glands

29. SALIVARY GLANDS

30. Parotid Gland
 The parotid gland is found below the level of the external
auditory canal, between the mandible and
the sternocleidomastoid Muscle.
Parotid Duct
 Arises from anterior border
 1.5 cm inferior to Zygomatic
arch
 4-6 cm in length

31. SUBMANDIBULAR GLAND
 It is a salivary gland located
beneath the floor of the
mouth
 It lies along the medial
aspect of the mandibular
body
 It is hook shaped
 It is divided into superficial
and deep lobes, which are
separated by the mylohyoid
muscle.
 Wharton’s duct: About 5cm
in length.

32. SUBLINGUAL GLANDS
 They lie anterior to the
submandibular gland under the
tongue, beneath the mucous
membrane of the floor of the
mouth.
 sublingual gland is
immediately lateral to the
submandibular duct
 The ducts of the sublingual
glands are called
Bartholin’s ducts.

34. BLOOD SUPPLY OF SALIVARY GLANDS
 Blood Supply to the parotid gland originate from
the external carotid artery.
 The submandibular and sublingual glands are
supplied by branches of the facial and lingual
arteries.
 Veins from the parotid gland drain into the external
jugular vein, and those from the submandibular
and sublingual glands drain into lingual and facial
veins.

37. FUNCTIONS
Protection . lubricant (glycoprotein)
Buffering (phosphate ions and bicarbonate)
Digestion
Antimicrobial. Lysozyme hydrolyzes cell walls of
some bacteria
Maintenance of tooth integrity (calcium and phosphate ions)
Tissue repair. Bbleeding time of oral tissues shorter than
other tissues
Taste. solubilizing of food substances that can be sensed
by receptors

38. • Composition of Saliva: 97-99.5% water
• pH 6.75-7.0
• Sodium, potassium, chloride, phosphate, and
bicarbonate
• Mucin
• Salivary amylase

39. 39
REGULATION OF SALIVARY SECRETION
Simple or unconditioned: The presence of food in
the mouth results in reflex secretion of saliva.
• Stimulus: presence of food in the mouth.
• Receptors: taste buds.
• Afferent: nerves from taste buds carry
impulses to salivary center.
• Centre: salivary center in medulla oblongata
(in brain stem).
• Efferent: autonomic nerves supplying salivary
glands.

40. CLASS ACTIVITY
Draw a diagram shows Salivary
glands nerves Innervations

41. QUESTIONS?