3. Its an oval shaped cavity
extend from the lips to the
palatoglossal arches
4. The entire oral cavity is
lined with mucous
membrane tissue. The
oral cavity consists of
the following two areas:
1. The vestibule is the
space between the teeth
and the inner mucosal
lining of the lips and
checks.
2. The oral cavity proper
is the space contained
within the upper and
lower dental arches.
5. Bones that contribute to
the skeletal framework
of the oral cavity or are
related to the anatomy
of structures in the oral
cavity include:
the paired
maxillae & palatine.
the unpaired
mandible, sphenoid
and hyoid bone.
6. Laterally : lips & gum
Medially : upper& lower
rows of teeth
Posteriorly : retromolar
area
7. lips
like the cheeks , the lips
are covered externally
by skin & internally by
mucous membrane (
labial mucosa).
the lips have a
muscular skeleton , the
orbicularis oris muscle .
the red zone of the lip (
the vermilion )which
devoid of hair& has a
rich capillary blood
supply-hence the color.
8. Gingivae (gums): are firmly
attached to the alveolar
margins of the jaws &
surround the necks of the
teeth. They consist of
dense vascular fibrous
tissue covered by
epithelium . the change
from alveolar mucosa to
gingival mucosa is marked
by an abrupt change of
color , from shiny alveolar
to pink opaque gingival.
9. Permanent dentition are as
follows
2 midline incisors
I canine
2 premolars
3 molars(8 each half,32 in all)
while the deciduous dentition
5 each half 20 in all
2 incisors
I canine
2 molars
10. the part which project into the
mouth is the crown which is covered
by enamel .
the part held in the jaw is the root
which is covered by cementum(
calcified tissue not bone).,
the junction between the 2 parts is
the cervical margin or neck,
The bulk of a tooth consist of
dentine( a hard avascular calcified
tissue penetrated by minute
canals((dentinal tubules)) )
inside the dentine is the pulp cavity
which filled by dental pulp (loose
connective tissue with nerves, blood
vessels & lymphatics ,all which get
access to the pulp through apical
foramina .
the tooth is slung in its bony socket
by the periodontal ligament which
shows as a clear interval between
tooth &bone shadows in a
11. It’s the mucosal surface
behind the 3rd molar tooth up
to the maxillary tuberosity .
there the mucosa overlies the
anterior border of the
ascending ramus of mandible
, separated from it by
pterygomandibular raphe
,where the buccinator&sup.
Constrictor muscles
decussate
12.
13.
14. Cheeks : are covered externally by skin &internally by
mucous membrane(buccal mucosa)& have a muscular
skeleton ,the buccinators,. Internally ,the pink mucosa
of the cheek adhere firmly to the buccinators muscle
15. few structural landmarks are visible.
The parotid duct opened as small papilla opposite the
maxillary 2nd molar tooth
a whitish line (linea alba) may be seen at a position
related to the occlusal plane of the teeth which is as a
result of continuous mild trauma during biting .
yellow patches ( Fordyce spots )representing ectopic
sebaceous glands , fold of mucosa covering
pterygomandibular raphe seen on opening of the
mouth widely behind the molar teeth .
16.
17.
18.
19.
The skeleton of the hard
palate is formed by the
palatine process of
maxilla
horizontal plates of
palatine bones ,
20. oral mucosa tightly adhered to
underlying periosteum.
In its more lateral regions it also
possesses a submucosa where the
main neurovascular bundles lie.
The periphery of the hard palate
surrounding the necks of the teeth
is termed gingiva & a midline palatal
raphe extending anteroposteriorly in
the midline is devoid of submucosa
where anteriorly behind the incisors
a small prominence ,incisive papilla ,
which covers the incisive fossa at the
oral opening of the incisive canal ,
radiating outwards from the palatal
raphe are irregular transverse ridges
or ruge .
its nasal surface covered with
respiratory epithelium while oral
mucosa is keratinized epithelium
21. Soft palate: its as mobile flap suspended from
the back of the hard palate , sloping down
between the oral & nasal part of the
nasopharynx.
it distinguished from hard palate by its change
in color to be darker red with a yellowish tint.
A median conical process , the uvula , projects
downwards from its posterior border. It
contains an aponeurosis ,muscular tissue ,
vessels, nerves ,lymphoid tissue & mucous
glands with some taste buds situated on its
oral surface.
The aponeurosis is thick in the anterior 2/3 of
the soft palate & thin as goes backwards , all
palatine muscles attached to the aponeurosis.
A thin fibrous palatine aponeurosis is
attached to the posterior border of the hard
palate which represent the expanded tendon of
tensor veli palatine muscles & provides the
fibrous skeleton of the soft palate that support
the palatine musculature.
22. The soft palate continues
posteriorly from the hard
palate &acts as a valve that
can be:
depressed to help close the
oropharyngeal isthmus.
elevated to separate the
nasopharynx from the
oropharynx.
23. Five muscles on each side
contribute to the formation and
movement of the soft palate.
tensor veli palatini m.
levator veli palatini m.
palatoglossus m.
Palatopharyngeus m.
musculus uvulae
All muscles of the soft palate are
innervated by the vagus nerve
[X] except for tensor veli
palatini, which is innervated by
the mandibular nerve [V3] (via
the nerve to medial pterygoid).
24.
25.
26. Floor of the mouth
a small horseshoe-shaped
region beneath the tongue
near the base of the tongue in
the midline , a fold of tissue
called the lingual frenlum.
sublingual papilla
submandibular salivary ducts
open into the mouth at this
papilla . on either side of the
sublingual papilla are the
sublingual folds, beneath
which lie the submandibular
ducts & sublingual glands.
The muscle forming the floor
of the mouth is mylohyoid
muscle & genohyoid m.
27.
28. It’s a bulky muscular organ
It has 2 parts ( oral &
pharyngeal )
has dorsal ,ventral surfaces,
root & apex
Oral part triangular in shape
demarcated from pharyngeal
part by V (shaped sulcus
terminalis)
Apex facing incisor tooth
Root attached to the mandible
& hyoid bone
29. PAPILLAE
The superior surface of the oral part of the
tongue is covered by hundreds of papillae:
filiform papillae
fungiform papillae
vallate papillae
foliate papillae
All except the filiform papillae have taste
buds on their surfaces.
PHARYNGEAL SURFACE
there are no papillea on pharyngeal surface.
the mucosa is irregular in contour bec. of
the many small nodules of lymphoid tissue
in the submucosa (lingual tonsil).
30.
31. Actions:
Intrinsic m.: are 4 groups , superior &
inferior longitudinal , the transverse &
the vertical muscles
*alter shape of tongue.
Extrinsic m.:
*These muscles protrude,retract,depress,
and elevate the tongue.
32. The extrinsic m composed of 4 pairs of muscles ( genioglossus, hyoglossus,
styloglossus, & palatoglossus )
narrow the oropharyngeal isthmus
action is to pull
the tongue Moving from side to side
upwards &
backwards
it depress the tongue
33.
34. Lymphatic drainage of the oral cavity:
The principal sites of drainage of lymphatic vessels from orodental tissues are the
submental
submandibular
jugulodiagastric & jugulo-omohyoidLN.
The cheek, upper lip& lateral parts of lower lip drains to the submandibular LN
while the central part of the lower lip drains to the submental LN.
Teeth usually drains directly into submandibular LN on the same side while the
mandibular incisor drains into submental LN. occasionally , lymph from molars
may pass directly into jugulodiagastric group of the nodes.
The lingual & palatal gingivae drains into the jugulodiagastric group of the nodes
either directly or indirectly through submandinlar nodes .
35.
36. A significant feature of the tongues lymph drainage which is through floor of
the mouth or pharyngeal wall, is that lymph from one side specially of the
posterior part may reach nodes of both sides ( in contrast to the blood supply
which remains unilateral ).
The tip may drain to submental nodes or directly to the deep cervical LN .
marginal lymphatics from the rest of the anterior part drains into ipsilateral
submandibular & then to the deep cervical LN but sometimes directly to the
deep cervical LN.
central lymphatics from anterior part descend between the geniglossi & drain
to the deep cervical LN of either side.
The posterior part drain directly & frequently bilaterally to the deep cervical
LN.
the deep cervical LN involved are the jugulodiagastric & jugulomohyoid nodes
.
all lymph from the tongue is believed to eventually drain through the jugulo-
omohyoid node before reaching the thoracic doctor the right lymphatic duct.
37.
38. Oral mucosa : the lining of the mouth , the oral mucosa is continuous with
the skin at the vermilion of the lip & with the pharyngeal mucosa at the
oropharyngeal isthmus .
it can be classified into:
masticatory mucosa covers the gingivae (gums) & a hard palate . its
epithelium is keratinized , pink in color & a submucosa is absent from the
gingivae & the midline palatine raphae , but present on the rest of the palate &
its firmly bound to the underlying bone or to the neck of the teeth .
Lining mucosa covers internal surface of the lips& cheeks ,floor of the mouth,
soft palate , ventral surface of the tongue & the alveolar process excluding
gingivae . its red color which have non-keratinized squamous epithelium
overlying a loosely fibrous & elastic lamina propria& the submucosa contains
some fat deposits & collections of minor mucous glands.
Gustatory mucosa covers the anterior 2/3 of the dorsum of the tongue .
the vermilion ( red zone) of the lip, the epithelium that attaches the tooth to
the gingiva( has features of both lining & masticatory mucosa).
