The oral cavity is divided into the oral cavity proper and the vestibule. The oral cavity proper contains the tongue and is bounded by the hard palate and dental arches. The vestibule is the space between the teeth and lips. Other structures include the lips, cheeks, gingiva, palate, and tongue. The tongue contains intrinsic and extrinsic muscles and is innervated by the hypoglossal nerve. The hard palate forms the roof of the mouth while the soft palate hangs from its posterior end and separates the nasal and oral cavities.

1. Oral Region
Dr. Haydar Muneer Salih

2. • Oral cavity is the first part of digestive
tract
1.Ingestion and swallowing
2.Speech
3.Respiration
• It is divided into two parts:
1. Oral cavity proper
2. The vestibule

3. Oral Cavity Proper
• It is the space between the upper and
the lower dental arches
• It is limited laterally and anteriorly by the
dental arches. The roof of the oral cavity
is formed by the palate. Posteriorly, the
oral cavity communicates with the
oropharynx (oral part of the pharynx).
When the mouth is closed and at rest,
the oral cavity is fully occupied by the
tongue

5. The oral vestibule
• The oral vestibule is the slit-like space
between the teeth and gingivae (gums)
and the lips and cheeks. The vestibule
communicates with the exterior through
the oral fissure (opening).
• The size of the oral fissure is controlled
by the circumoral muscles

7. Lips
• Each lip is largely composed of orbicularis oris
muscle. In addition it contains labial (mucous)
glands and blood vessels. It is lined externally
by skin which contains sweat glands and
sebaceous glands with hair follicles (The hairs
are thicker and more numerous in adult
males). They are lined internally with mucus
membrane. The mucocutaneous junction
appears as a reddish pink area visible
externally

8. • Arterial supply of lips is derived from superior
and inferior labial arteries, branches of facial
artery.
• Lymphatics of lips drain into the following
lymph nodes:
a. Submandibular lymph node
b. Submental lymph nodes
• Skin of lips is innervated by branches of
infraorbital nerve (upper lip) and mandibular
nerve (lower lip). Muscles are supplied by facial
nerve.

14. Cheek
Cheeks are the fleshy flaps which lie over maxilla
and mandible and form a large part of the face.
Each cheek is continuous in front with the lip.
The junction between the two is marked by the
nasolabial sulcus or the furrow which extends
from the side of the nose to the angle of the
mouth. Like the lips the cheeks are lined
externally by skin and internally by mucous
membrane

15. From superficial to deep:
1. Skin
2. Superficial fascia containing muscles of facial
expression
3. Buccinator
4. Buccal pad of fat
5. Buccopharyngeal fascia
6. Submucosa, containing buccal (mucous)
glands
7. Mucous membrane
Structure & layers of the cheek:

17. • Arterial supply of cheeks is derived from
buccal branch of maxillary artery.
• Lymphatics from cheek drain into
submandibular and preauricular lymph
nodes.
• Skin of cheek is innervated by :
zygomaticofacial and infraorbital branches
of maxillary nerve, mucus membrane is
supplied by buccal branch of mandibular
nerve. Muscles are supplied by facial nerve

18. Oral Mucosa
The mucosal lining of oral cavity continues
with the skin of lips anteriorly and mucosa
of oropharyx posteriorly. It can be divided
into three types according to the
anatomical location and function
1.Lining mucosa
2.Masticatory mucosa
3.Specialized mucosa

19. 1.Lining mucosa:
It consists of non-keratinized stratified
squamous epithelium. It lines the inner
aspect of lips and cheeks, covers soft
palate, ventral surface of tongue, floor of
mouth and lower part of upper and lower
alveolar processes (jaws). It overlies a
loose layer of lamina propria and has
submucosa which contains fat and minor
salivary glands

21. 2.Masticatory mucosa:
• It is the mucosa that lines the upper part
of alveolar process, neck of teeth and the
hard palate. It consists of keratinized
stratified squamous epithelium with
minimal lamina propria that has
connective tissue fibers which adhere
the epithelium to the underlying bone.
There is no submucosa. This modification
• allows the epithelium to bear the stress
of mastication

23. Gingiva (Gum(
Gingiva is the masticatory mucosa that covers
the alveolar processes of maxilla (upper jaw)
and mandible (lower jaw) and surrounds the
neck of teeth. It can be divided into two parts:
1. Attached gingiva: It is firmly bound to the
periosteum of the alveolar bone and tooth.
2. Free or unattached gingiva: It is the distal 1
mm margin of gingiva that surrounds the neck
of the tooth and is not attached to the bone.

25. • The gingival tissues derive their blood supply
from branches of maxillary artery (supplies the
buccal and labial surfaces) and lingual artery
(supplies the lingual surfaces).
• Lymphatics from gingivae drain into
submandibular lymph nodes.
• Gingivae of upper jaw are supplied by
branches of maxillary nerve while of lower jaw
are supplied by branches of mandibular nerve

26. 3.Specialized mucosa:
It is the mucosa which covers the dorsal
surface of tongue. It consists of stratified
squamous non-keratinized epithelium
which is directly adherent to the
underlying muscles. There is no
submucosa. It gives rise to a number of
projections called lingual papillae which
are described ahead with tongue.

28. TONGUE
• Tongue is a mass of striated muscle covered
with mucous membrane. The muscles attach
the tongue to the styloid process and the soft
palate above and to the mandible and the
hyoid bone below, the tongue is divided into
right and left halves by a median fibrous
septum
• The V-shaped sulcus serves to divide the
tongue into the anterior two thirds, or oral
part, and the posterior third , or pharyngeal
part.

29. • The mucous membrane covering the
posterior third of the tongue is devoid of
papillae but has an irregular surface,
caused by the presence of underlying
lymph nodules, the lingual tonsil.
• the undersurface of the tongue is
connected to the floor of the mouth by a
fold of mucous membrane, the frenulum
of the tongue

31. Muscles of the Tongue
The muscles of the tongue are divided into two
types: intrinsic and extrinsic.
1-Intrinsic Muscles
These muscles are confined to the tongue and
are not attached to bone. They consist of
longitudinal, transverse, and vertical fibers.
Nerve supply: Hypoglossal nerve
Action: Alter the shape of the tongue

33. 2-Extrinsic Muscles
These muscles are attached to bones and
the soft palate.
They are the genioglossus,
the hyoglossus,
the styloglossus,
and the palatoglossus.
Nerve supply: Hypoglossal nerve
Except the palatoglossus which innervated
by pharyngeal plexus ( CN X)

35. Sensory Innervation
Anterior two thirds: Lingual nerve branch
of mandibular division of trigeminal nerve
(general sensation) and chorda tympani
branch of the facial nerve (taste)
Posterior third: Glossopharyngeal nerve
(general sensation and taste)
A small posterior region receives sensory
innervation from CN X.

37. Blood Supply
The lingual artery, the tonsillar branch of the
facial artery, and the ascending pharyngeal
artery supply the tongue.
The veins drain into the internal jugular vein.
Lymph Drainage
Tip: Submental lymph nodes
Sides of the anterior two thirds: Submandibular
and deep cervical lymph nodes
Posterior third: Deep cervical

39. Movements of the Tongue
Protrusion: The genioglossus muscles on both
sides acting together
Retraction: Styloglossus and hyoglossus muscles
on both sides acting together
Depression: Hyoglossus muscles on both sides
acting together
Retraction and elevation of the posterior third:
Styloglossus and palatoglossus muscles on both
sides acting together
Shape changes: Intrinsic muscles

41. PALATE
It is an osteomuscular partition between
nasal and oral cavities. It also separates
nasopharynx from oropharynx.
The palate consists of two parts:
1. Hard palate: It forms the anterior 2/3rd
of the palate.
2. Soft palate: It forms the posterior 1/3rd
of the palate

43. • The hard palate forms a partition between the
nasal and oral cavities.
• The anterior 3/4th is formed by the palatine
processes of the maxillae and the posterior
1/4th
by the horizontal plates of the palatine
bones.
• The superior surface of hard palate forms the
floor of nasal cavity and is lined by the ciliated
pseudostratified columnar epithelium.
• The inferior surface of hard palate forms the
roof of oral cavity and is lined by masticatory
mucosa. It presents with a median palatine
raphe

46. • Arterial supply of hard palate is dervied
from greater palatine artery, branch of
maxillary artery and ascending palatine
branch of facial artery. The veins drain
into pterygoid plexus of veins.
• Nerve supply of hard palate is derived
from greater palatine and nasopalatine
branches of maxillary nerve through
pterygopalatine ganglion.

48. Soft Palate
The soft palate is a mobile muscular fold
suspended from the posterior border of
the hard palate like a velum. It is lined by
nonkeratinized stratified squamous
epithelium which encloses muscles,
vessels, nerves, lymphoid tissue and
mucous glands. It appears red in
comparision with the hard palate which is
pink. It separates the nasopharynx from
oropharynx.

49. • On each side, from the base of uvula, two
curved folds of mucous membrane extend
laterally and downwards along the lateral wall
of oropharynx.
These are:
i. Palatoglossal fold
It is the anterior fold which merges inferiorly
with the sides of the tongue at the junction of
its oral and pharyngeal parts.
ii. Palatopharyngeal fold
It lies posterior to the palatoglossal fold and
merges inferiorly with the lateral wall of the
pharynx.

51. Muscles of the Soft Palate
The soft palate consist of five pairs of
muscles:
Tensor veli palatini
Levator veli palatini
Palatoglossus
Palatopharyngeus
Musculus uvulae

53. Functions of the Soft Palate
1. Separates the oropharynx from
nasopharynx during swallowing so that
food does not enter the nose.
2. Isolates the oral cavity from oropharynx
during chewing so that breathing is
unaffected.
3. Helps to modify the quality of voice, by
varying the degree of closure of the
pharyngeal isthmus.

54. Arterial Supply of Soft Palate
It is supplied by the following arteries:
1. Ascending palatine artery, branch of facial
artery.
2. Palatine branch of ascending pharyngeal
artery.
3. Greater palatine artery, branch of maxillary
artery.
Venous Drainage of Soft Palate
Veins drain into the pterygoid plexus of veins.

56. Lymphatic Drainage of Soft Palate
Lymphatics from soft palate drain into
the following nodes:
1. Retropharyngeal nodes.
2. Deep cervical lymph nodes

57. Nerve Supply of Soft Palate
1. Motor supply: All muscles of palate are
supplied by cranial part of accessory nerve via
pharyngeal plexus except tensor veli palatini
which is supplied by nerve to medial pterygoid, a
branch of mandibular nerve.
2. Secretomotor Supply to Palatine Glands
(preganglionic and postganglionic fibers).
3. Sensory supply: The afferents pass to
a. Greater and lesser palatine nerves
b. Sphenopalatine nerves
c. Glossopharyngeal nerves