3. The oral cavity is conveniently divided by the
arch formed by the teeth and gums into:
1. Oral Vestibule
- lies between the
gums and the teeth.
2. Oral Cavity Proper
- lies behind and
within the arch of
teeth.
5. Boundaries:
1. Anteriorly by the
lips,
2. Laterally by the
cheeks,
3. Superiorly by the
mucolabial and
mucobuccal folds,
and
4. Posteriorly and
medially by the teeth
and gums.
7. Boundaries:
1. Anteriorly and
laterally by the teeth
and gums,
2. Superiorly by the
palate (hard and
soft),
3. Inferiorly by the
tongue and the floor
of the mouth, and
4. Posteriorly by the
opening into the
pharynx.
8. The Sublingual Region
Characteristic
features:
1. Anterior 2/3 of
the tongue,
2. Lingual frenulum,
3. Lingual vein,
4. Sublingual
caruncle,
5. Sublingual folds
6. Fimbriated fold
9.
10. Gums and Gingivae
- consist of dense vascular fibrous tissue which
is covered by mucous membrane and is
attached to the alveolar margins of the jaw.
- they are continuous with the mucosa of the
oral vestibule externally and the palate or the
floor of the mouth internally.
11. Hard and Soft Palate
The palate forms the superior wall or the roof of
the oral cavity proper. It is composed of the
hard palate which has an osseous base, and
behind, a soft palate composed of fibrous
tissue.
13. - Covered by mucoperiosteum and forms a
partition between the oral and nasal cavities.
- mucoperiosteum is thin in the middle but thicker
at the sides due to the presence of numerous
glands
- formed by the palatine process of the maxilla
and the horizontal plate of the palatine bone.
14. Characteristic Features:
1. Median raphe is a
longitudinal ridge
extending from the
uvula to the incisive
papilla.
2. Incisive papilla is a
small projection of the
mucosa indicating the
location of the incisive
foramen and the
anterior limit of the
median raphe.
15. 3. Transverse palatine
process or palatine rugae
are about six distinct
elevation crossing the
anterior part of the hard
palate.
4. Fovea palatine are small
inconstant pits on the
posterior margin of the
hard palate on either
side of the median
raphe.
17. Is the posterior movable portion of the palate,
extending from one side of the pharynx to the
other, and attached to the posterior border of
the hard palate.
18. Characteristic Features:
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.
19. Muscles of the Soft Palate
Muscle Origin Insertion Action
Palatopharyn- Palatal Lateral wall of Elevates the
geus aponeurosis the pharynx pharynx and
and posterior larynx
border of the Closes the
thyroid cartilage oropharyngeal
isthmus
Palatoglossus Palatal Dorsum and Closes the
aponeurosis lateral aspect of oropharyngeal
the tongue isthmus
Uvular Posterior nasal Uvula Raises the
spine uvula to help
seal oral from
nasal pharynx
20. Muscles of the Soft Palate
Muscle Origin Insertion Action
Levator veli Medial aspect Directly into Elevates
palatini of the auditory the palatine palate during
tube aponeurosis swallowing,
yawning
Tensor veli Lateral aspect Tendon hooks Tenses the
palatini of the under hamulus palate and
membranous and inserts opens the
portion of the into the palatal mouth of
auditory tube, aponeurosis auditory tube
scaphoid fossa during
of the swallowing
sphenoid bone and yawning
22. • A mobile mass of muscles lying on the floor of
the mouth and associated with the function of
taste, chewing, swallowing, and speaking.
23. Characteristic features:
1. Root is the lower
portion of the posterior
half of the tongue
through which the
extrinsic muscles,
blood vessels and
nerves become
connected with the
organ. It is attached to
the mandible and the
hyoid bone
24. 2. Body anterior part of the
tongue, made up of
interlacing skeletal
muscles.
3. Margins are the lateral
portion of the tongue,
free and blunt, in relation
to the gums and teeth.
4. Tip or apex is the pointed
and free anterior end.
5. Inferior surface is seen
when the tongue is
turned upwards.
25. 6. Dorsum linguae is slightly
convex antero-posteriorly,
divided into 2 parts by a V-
shaped groove – the SULCUS
TERMINALIS or LINEA
TERMINALIS.
Parts:
a. Palatine part is visible
when the mouth is opened,
covered by papillae.
b. Median sulcus is a faint
groove separating the
palatine part into
symmetrical parts.
c. Foramen caecum is a
small pit at the apex of the
sulcus terminalis.
d. Pharyngeal part is the
posterior 2/3s of the tongue
which contains serous glands
and nodules of lymphoid
tissue – LINGUAL FOLLICLES.
e. Glosso-epiglottic fold is
the reflection of the mucous
membrane of the tongue on
to the epiglottis producing
elevation.
27. 1. Vallate or circumvallate papillae are the largest,
numbering from 7-12, and are arranged in front of
the sulcus terminalis.
2. Fungiform papillae are fewer in number and are
limited to the tip and margins of the tongue.
3. Filiform papillae are the smallest and the most
numerous, scattered all over the anterior 2/3 of
the dorsum of the tongue.
28. The Taste Buds
- are receptor organs for the special
sensation of taste. They are pale oval bodies
most of which are located surrounding the
vallate papillae; a few are found on the
fungiform and foliate papillae. A few taste
buds are scattered through the epithelium of
the oral surface of the soft palate, the
posterior wall of the pharynx, and the
epiglottis.
29. The Muscles of the Tongue
Extrinsic muscles are responsible for changing
position of the tongue.
Muscle Origin Insertion Action
Genioglossus Genial tubercle Tongue Retract and
of mandible depress the
tongue
Hyoglossus Hyoid bone Posterior half of Depress the
the side of the tongue
tongue
Styloglossus Styloid process Whole length of Pull the tongue
of temporal the tongue upwards and
bone backwards
30. The Muscles of the Tongue
The Intrinsic Muscles:
1. Superior and inferior longitudinal muscles
- Located close to the dorsum of the tongue
- Shorten the length of the tongue and to curl the tip of
the tongue and back.
2. Transverse muscles
- narrows the tongue.
3. Vertical muscles
- flattens the tongue.
31.
32.
33. A Summary of the
Actions of the Tongue
1. Protrussion : genioglossus
2. Retrussion : hyoglossus, styloglossus,
genioglossus
3. Depression : genioglossus, hyoglossus
4. Elevation : styloglossus
5. Shortening : longitudinal intrinsic fibers
6. Narrowing : transverse intrinsic fibers
7. Flattening : vertical intrinsic fibers
35. Paralyzed Tongue
a fractured mandible may damage the
hypoglossal nerve to pull the tongue to the
same side. General anesthesia results in
looseness, or flaccidity, of muscles. A
paralyzed or flaccid tongue tends to fall back
into the airway, causing suffocation, unless a
patent airway is maintained.
36. Tongue Tie
A large lingual frenulum can limit the
mobility of the tongue and interfere with
speech. The condition is easily repaired
by cutting the frenulum (lingual
frenectomy).
41. The Parotid Gland
The parotid gland is one of
the three major salivary
glands that produce and
secrete saliva for the
oral cavity.
weight: about 14 to 28 g.
color :yellowish in the
fresh state
composition: serous
secreting units
42. Location and Relations
of the Parotid Gland
A. Anterior surface: lies
against the posterior
border of the ramus of
the mandible
B. Posterior surface: on
the external auditory
meatus and
sternocleidomastoid
muscle
43. B. Superficial surface:
lobulated, covered by
skin, fascia, lymph
nodes, and facial
branches of the great
auricular nerve.
C. Deep surface: styloid
process and its
muscles as well as
under the mastoid and
sternocleidomastoid
muscles.
44. Capsule of the Parotid Gland
-The gland is wrapped in a fibrous capsule, which is
continuous with the deep investing fascia of the
neck.
-The stylomandibular ligament is an anterior thickening
of the capsule, which runs from the styloid process
to the angle of the mandible. –
-It separates the parotid gland from the infratemporal
fossa anteriorly and separates the parotid gland
from the submandibular gland inferiorly and
anteriorly.
45. The Parotid Duct
From the rostral border of
the gland, crosses
masseter muscle, turns
inward to pierce the fat
pad of the cheek and
then the buccinator
muscle, to open into
the mouth opposite
the second maxillary
molar. Approximately 5
cm. long.
47. 1. A viral inflammation of the parotid gland
(mumps) causes it to swell, resulting to pain
on movement of the jaw.
2. Abcesses or cysts of the gland may result in
pressure to the facial nerve
3. Stones or calculi in the duct can block it,
causing painful swelling of the gland.
49. Type:
It is a mixed serous and mucous secreting
gland.
Location:
It is found partly in the submandibular fossa
below the mylohyoid muscle and partly in
the floor of the mouth.
50. Duct:
The submandibular duct (Wharton’s) arises from
the medial surface of the gland and
accompanies it under the mlohyoid muscle; it
passes diagonally across the medial aspect of
the sublingual gland and adheres to it. It opens
at the sublingual papillae (sublingual caruncle)
beside the base of the lingual frenulum.
52. The smallest of the three major salivary glands
and rests upon the mylohyoid muscle in the
sublingual fossa close to the symphysis. It is
primarily a mucous secreting gland.
53. Location:
The gland, indicated by the subligual fold is
found between the alveolus and the anterior
part of the tongue.
Ducts:
The gland has many lesser sublingual ducts
(Rivini’s) that opens separately at the floor of
the mouth and a greater sublingual duct
(Bartholin’s) that opens on the sublingual
caruncle together with the Wharton’s duct.
55. The Accessory Glands
Beside the main salivary glands, many others
exists: some in the tongue, others around and
in the palatine tonsil between its crypts, with
the large number in the soft palate, the
posterior part of the hard palate, the lips and
the cheeks. These are similar in structure to
larger salivary glands and are mainly mucous
type.
