Transcript OraL Cavity

Oral Cavity
CLERK AILEEN DOLES GUERZON
Overview
 Functions
 Anatomy
 Embryology
 Histology
 Physiology
 Clinical Evaluation of the Nose
 Common Diseases and Management
ANATOMY
Oral Region
 oral cavity
 teeth
 gingivae
 tongue
 palate
 palatine tonsils
Oral Cavity

where food and drinks are tasted and savored and where
mastication and of lingual manipulation of food occur
 consists of 2 parts:
 oral vestibule
 the slit-like space between the teeth and
buccal gingiva and the lips and cheeks
 oral cavity proper
 the space between the maxillary and
mandibular alveolar arches and the teeth they
bear, roof of the oral cavity is formed by the
palate, posteriorly, communicates with the
oropharynx

rima oris: opening of the mouth, controlled by the orbicularis oris,
the buccinator, risorius, and depressors and elevators of the lips
ORAL VESTIBULE
Lips

are used for grasping food, sucking liquids, keeping food out of the
oral vestibule, forming speech, and osculation (kissing)

mobile, musculofibrous folds surrounding the mouth, extending
from the nasolabial sulci and nares laterally and superiorly to the
mentolabial sulcus inferiorly

contain the orbicularis oris and superior and inferior labial
muscles, vessels, and nerves

covered externally by skin and internally by mucous membrane
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transitional zone of the lips (commonly considered by itself to be
the lip), ranging from brown to red, continues into the oral cavity
where it is continuous with the mucous membrane

labial frenula are free-edged folds of mucous membrane in the
midline, extending from the vestibular gingiva to the mucosa of the
upper and lower lips
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superior and inferior labial arteries which are branches of the
facial arteries, anastomose with each other in the lips to form an
arterial ring
Cheeks
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form movable walls of the oral cavity
external aspect of the cheeks constitutes
the buccal region, bounded anteriorly by the
lips and chin, superiorly by the zygomatic
region, posteriorly by the parotid region, and
inferiorly by the inferior border of the
mandible
buccinators are the principal muscles of the
cheeks
numerous small buccal glands lie between the
mucous membrane and the buccinators
buccal fat-lies superficial to the buccinator,
are proportionately much larger in infants,
presumably to reinforce the cheeks and keep
them from collapsing during sucking
supplied by buccal branches of the maxillary
artery and innervated by buccal branches of
the mandibular nerve
Gingiva
are composed of
fibrous tissue covered
with mucous membrane
gingiva proper is firmly
attached to the alveolar
processes of the jaws
and the necks of the
teeth, normally pink,
stippled, and
keratinizing
alveolar mucosa
(unattached gingiva) is
normally shiny red and
non-keratinizing
Teeth
 can either be deciduous (primary) or permanent
(secondary)
 children have 20 deciduous teeth; adults normally
have 32 permanent teeth (numbered superiorly R
to L, inferiorly L to R)
 before eruption, the developing teeth reside in
the alveolar arches as tooth buds
Parts and Structure of the Teeth
periodontium -composed of collagenous fibers that extend between
the cement of the root and the periosteum of the alveolus
TABLE 22-1. APPROXIMATE TIME
SCHEDULE FOR TOOTH ERUPTION
Deciduous
Medial incisors
Lateral incisors
First molar
Canine
Second molar
Age
(months)
7
9
15
18
20-24
Permanent
First molar
Medial incisors
Lateral incisors
First premolar
Canine
Second premolar
Second molar
Third molar
Age(years)
6
6-7
8-9
10-11
10.5-11.5
11-12
12-13
17-25
TONGUE
Surface Anatomy
 papillae -cover the anterior 2/3 of the
tongue, including filiform (no taste function)
fungiform (diffuse), and foliate (lateral
tongue), and circumvallate papillae (junction
of the anterior and posterior portions of the
tongue)
 sulcus terminalis - groove along the margin of
the circumvallate papillae.
 foramen cecum - pit at the junction of the
sulcus terminalis from which the embryologic
thyroid begins its descent (etiology of
thyroglossal duct cyst)
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frenulum - anterior fold of mucous membrane
attaches the anteroinferior aspect of the
tongue to the floor mouth and gingiva.
Wharton's ducts open on either side of the
frenulum. May be congenitally short (tonguetied)
lingual tonsil - lymphoid tissue extending over
the base of the tongue (considered to be in
oropharynx). Size varies among individuals.
Blood supply from lingual artery and vein
valleculae -depressions on either side of the
midline glossoepiglottic fold extending to the
level of the hyoid bone (considered to be in
oropharynx)
Tongue: Surface Anatomy
LINGUAL TONSILS
SULCUS TERMINALIS
VALLECULA
Nerve Supply to the Tongue
Muscles of the Tongue
1. Extrinsic muscles of the tongue
(cranial nerve XII): Include the
geniglossus, hyoglossus, styloglossus,
and palatoglossus.
2. Intrinsic muscles (cranial nerve
XII): Include superior and inferior
longitudinal, vertical, and transverse.
3. Fibrous septa (septum linguae):
Defines midline and contains a
triangular fat pad that is visualized
on axial computed tomography (CT)
scan.
Salivary Glands

are the parotid, submandibular, and sublingual glands that secrete clear,
tasteless, odorless viscid fluid called saliva keeps the mucous membrane of
the mouth moist, lubricates the food during mastication, initiates the
digestion of starches

plays significant roles in the prevention of tooth decay and in the ability to
taste.
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small accessory salivary glands are scattered over the palate, lips, cheeks,
tonsils, and tongue
Salivary Ducts
1. Parotid (Stensen's): Orifice is lateral to second molars .
2. Submaxillary (Wharton's): Orifice is in midline floor of mouth adjacent to
lingual
frenulum.
3. Sublingual (Rivinus's): Multiple orifices draining into floor of mouth or into
submaxillary duct.
Saliva
 Daily secretion: 1500 mL/day

When unstimulated, 2/3 is secreted by submaxillary glands,
when stimulated, two-thirds by parotid glands.
 99.5% water with only 0.5% organic/inorganic
solids:
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Na: 10 mEq/L
K: 26 mEq/L,
Cl: 10 mEq/L
HCO3: 30 mEqlL
pH = 6.2 to 7.4.
Organic component: glycoprotein, amylase
Muscles of Mastication
Masseter, temporalis, lateral pterygoid, medial
pterygoid
Palate
FORAMINA OF THE PALATE
 Greater palatine foramen: Conveys
descending palatine branch of nerve V2 to
innervate palate as well as descending
palatine artery (third division of maxillary
artery); is 1 cm medial to second molar
 Accessory palatine foramen: Posterior to
greater palatine foramen, conveys lesser
descending palatine artery to soft palate
 Incisural foramen: Lies in midline of
anterior palate, transmits incisural artery
to anterior septum
Embryology
 derived from the embryonic fore gut
 mouth forms from the primitive
stomodeum
 upper lips formed by elements of the
medial and lateral nasal processes and the
maxillary processes
 premaxilla formed by medial nasal process
 lip muscles from 2nd branchial region
 2 parts of the palate:
 pre-maxilla- incisors
 posterior palate –hard and soft palate
DISEASES OF THE ORAL
CAVITY
Cleft LIP -/+ PALATE
 80% unilateral
 Classification of CL
+/- CP
 CL +/- P
 CP
 Unilateral
 Bilateral
 Complete
 Incomplete
Angular Cheilitis
 Erythema with
maceration and
crusting at the
commissures with
burning sensation
and dryness due
to iron and
riboflavin
deficiency,
mechanical
trauma
Leukoplakia
 White plaque firmly
attached to oral
mucosa caused by
chronic local
friction
Squamous Cell Carcinoma
 Appear as an erosion
or an ulcer with
irregular papillary
surface, hard base
on palpation. The
cause is
multifactorial
Mucocele
 Mucous cysts resulting from duct rupture
or ductal obstruction of minor salivary
glands due to mucous plug.
Hemangioma
 Elevated, firm,
painless tumor with
a reddish color
involving the palate,
tongue, gingiva and
lips
Herpetic Gingivostomatitis
 Relatively common
viral infection of the
oral mucosa.
 Affected mucosa is
red and edematous
with numerous
coalescing vesicles
which rapidly rupture
leaving painful small,
round, shallow ulcers
covered by yellow
fibrin
Papilloma
 Exophytic, painless,
pedunculated growth,
characteristically it
has a white or normal
color with fingerlike
projection that form
a cauliflower pattern
Gingivitis
 Interdental papillae
and marginal gingiva
appear diffuse, red,
swollen and
significantly
increased in size.
 Etiology maybe due
to dental plaque,
systemic disease or
drug induced.
Pyogenic Granuloma
 a common reactive
neoformation of the
oral cavity, which is
composed of
granulation tissue
and develops in
response to local
irritation or trauma
KISSING TONSILS
 It is unusual for
tonsils to touch or
meet in the midline
without protrusion
of the tongue.When
tonsils meet in the
midline or overlap,
they are called
"kissing tonsils".
Lichen Planus
 Chronic
inflammatory
disease of the oral
mucosa where white
padules coalesce to
form a network of
lines ( Wickman’s
Striae ) 6 forms are
recognized
Steven’s-Johnson Syndrome
 Extensive vesicle formation followed by
painful erosion covered by grayish white or
hemmorrhagic pseudomembranes. It is usually
drug induced
Vincent’s Angina

an acute necrotizing infection of the
pharynx caused by a combination of fusiform
bacilli (Fusiformis fusiformis) and
spirochetes (Borrelia vincentii )

unilateral sore throat that increases in
intensity over several days with an
associated referred earache on the same
side, a bad taste in the mouth and a fetid
bad breath

On PE, there is a deep well circumscribed
unilateral ulcer of one tonsil. The base of
the ulcer is gray and bleeds easily when
scraped with a swab. There may also be an
associated submandibular lymphadenopathy
Angioedema
 characterized by painless,
nonpruritic, nonpitting, and
well-circumscribed areas of
edema due to increased
vascular permeability.
Angioedema is most
apparent in the head and
neck, including the face, lips,
floor of the mouth, tongue,
and larynx, but edema may
involve any portion of the
body. In advanced cases,
angioedema progresses to
complete airway obstruction
and death caused by
laryngeal ed
Torus Palatinus
 a common developmental
exostosis or outgrowth of
the bone of the hard palate
that manifests itself in
adults at about the age of
30. It is more common in
women and is always located
in the midline. It is an
extension of the bone of the
hard palate and and not a
true neoplasm. It is benign
and rarely needs
treatment. Occasionally, it
is removed because it
interferes with the fitting
of dentures
Acute Tonsillitis
usually begins with high temperature
and possibly chills, especially in
children. The patient complains of a
persistent pain in the throat, and pain
radiating to the ear on swallowing.
Opening the mouth is often difficult
and painful, the tongue is coated, and
there is a mouth odor. The patient
may also complain of headache, thick
speech, marked feeling of malaise, as
well as swelling and tenderness of the
neck glands (lymph nodes). Both
tonsils and the surrounding area
including the posterior pharyngeal wall
are deep red and swollen. Later,
whitish spots (follicles) form on the
tonsils, hence the name follicular
tonsillitis. There is also swelling of the
neighboring organs such as the faucial
pillars, the uvula, and the base of the
tongue