2. Lips and Cheeks
• The lips are musculofibrous folds
that are connected to the gums by
superior and inferior frenula.
• The median part of the upper lip
shows a shallow external groove,
the philtrum.
• The lips consist (from external to
internal) chiefly of skin
3. • The three layers forming the skin can be
identified in all skin sections.
• The epithelium forming the surface layer,
the epidermis, is usually the darkest layer
visible. Sublayers are visible in the
epidermis.
• At the transition from the epidermis to the
dermis, staining will become lighter. The
lighter stained layer, the dermis, consists
of dense irregular connective tissue.
• The dermis is much thicker than the
epidermis. In thick skin, dermal papillae
create a very irregular border between
epidermis and dermis.
• The hypodermis is the lightest layer visible
and consists mainly of adipose tissue.
Dense connective tissue strands may
extend from the dermis deep into the
hypodermis.
4. • Tongue
• The tongue situated in the floor of
the mouth, is attached by muscles to
the hyoid bone, mandible, styloid
processes, and pharynx.
• The tongue is important in taste,
mastication, swallowing, and
speech.
• It is composed chiefly of skeletal
muscle, is partly covered by mucous
membrane, and presents a tip and
margin, dorsum, inferior surface,
and root
• The tip, or apex, usually rests
against the incisors and continues
on each side into the margin.
• The oral part of the dorsum may
show a shallow median groove.
5. • The mucosa has numerous minute
lingual papillae:
• (1) the filiform papillae, the
narrowest and most numerous;
Filiform Papillae
• = plush of tongue
• Parallel rows
• Primary columnar elevation of lamina
propria
• 5 – 30 tall secondary papillae
• Epithelium over papillae – end in
tapered points
• Hard & scaly (not cornified)
• FILIFORM PAPILLAE OF THE
TONGUE
Stained with H&E
• 1 - epithelium covering papilla
(stratified squamous keratinizing)
2 - keratinized layer of the epithelium
3 - core of the papilla (lamina
propria of the mucosa of dorsal
surface of the tongue)
4 - tongue muscles
6. (2) Fungiform Papillae
the fungiform papillae, with rounded
heads and containing taste buds
Knob-like
Scattered, single, among filiform papillae
Larger & fewer than filiform papillae
Narrow stalk, rounded top
Size: 1.8 mm. high; 1 mm.
Has 1 to several taste buds
Fungiform Papillae
Stained with H&E
1 - epithelium covering papilla
(stratified squamous nonkeratinizing)
2 - core of the papilla (lamina propria
of the mucosa of dorsal surface of the
tongue)
3 - taste buds
7. CIRCUMVALLATE PAPILLAE OF THE TONGUE
much larger than any of others
about 8-12 located in post region of
tongue, just next to sulcus terminalis
have deep furrow’s next to each
papillae = where von Ebner’s glands
open
Von Ebner’s glands = serous lingual
glands
Stained with H&E
1 - epithelium covering papilla
(stratified squamous nonkeratinizing)
2 - core of the papilla (lamina propria of the
mucosa of dorsal surface of the tongue)
3 - taste buds
8.
9. Tooth Structure
• Two main regions – crown and the root
• Crown – exposed part of the tooth above
the gingiva (gum)
• Enamel – acellular, brittle material
composed of calcium salts and
hydroxyapatite crystals is the hardest
substance in the body
– Encapsules the crown of the tooth
• Root – portion of the tooth embedded in
the jawbone
10. Tooth Structure
• Neck – constriction where the crown and
root come together
• Cementum – calcified connective tissue
– Covers the root
– Attaches it to the periodontal ligament
• Dentin – bonelike material deep to the
enamel cap that forms the bulk of the
tooth
• Pulp cavity surrounded by dentin that
contains pulp
• Pulp – connective tissue, blood vessels,
and nerves
• Root canal – portion of the pulp cavity
that extends into the root
• Apical foramen – proximal opening to
the root canal
• Odontoblasts – secrete and maintain
dentin throughout life
11. • TOOTH DEVELOPMENT -
FORMATION OF DENTAL
TISSUES
Stained with H&E
• 1 - ameloblasts (former external
cells of the enamel organ)
2 - enamel
3 - dentine (predentine)
4 - odontoblasts (cells which
covered the top of dental papilla)
5 - dental pulp (former dental
papilla)
TOOTH DEVELOPMENT -
FORMATION OF DENTAL TISSUES
Stained with H&E
1 - ameloblasts
2 - enamel
3 - dentine (predentine)
4 - odontoblasts
5 - dental pulp
border between enamel and dentine
is marked with dot line
12. Salivary Glands
• Produce and secrete
saliva that:
– Cleanses the mouth
– Moistens and dissolves
food chemicals
– Assist in bolus formation
– Contains enzymes that
break down starch
• Three pairs of extrinsic
glands – parotid,
submandibular, and
sublingual
• Intrinsic salivary glands
(buccal glands) –
scattered throughout
the oral mucosa
13. • Parotid – lies
anterior to the ear
between the
masseter muscle
and skin
– Parotid duct –
opens into the
vestibule next to
the second upper
molar
• Submandibular – lies
along the medial aspect of
the mandibular body
Its ducts open at the
base of the lingual
frenulum.
• Sublingual – lies anterior
to the submandibular gland
under the tongue
It opens via 10-12
ducts into the floor of
the mouth.
17. • SUBLINGUAL SALIVARY GLAND
Stained with H&E
• 1 - mucous part of mixed secretory unit
2 - serous part of mixed secretory unit
3 - serous secretory unit
4 - mucous secretory unit
5 - intercalated excretory duct
6 - striated excretory duct
7 - interlobular excretory duct
8 - interlobular connective tissue septa
SUBLINGUAL SALIVARY GLAND
Stained with H&E
1 - mucous part of mixed secretory
unit
2 - serous part (serous demilune) of
mixed secretory unit
3 - serous secretory unit
4 - mucous secretory unit
5 - myoepithelial cells
18. SUBMANDIBULAR SALIVARY
GLAND
Stained with H&E
1 - serous secretory unit
2 - mixed secretory unit
3 - intercalated excretory
duct
4 - striated excretory duct
5 - interlobular excretory
duct
6 - interlobular
connective tissue septa
7 - mucous part of mixed
secretory unit
8 - serous part (serous
demilune) of
mixed secretory unit
19. • SUBMANDIBULAR
SALIVARY GLAND
Stained with H&E
• 1 - serous secretory unit
2 - mixed secretory unit
3 - intercalated excretory
duct
4 - striated excretory duct
20. Esophagus
• The part of the gastrointestinal tract called
the esophagus is a muscular tube whose
function is to transport foodstuffs from the
mouth to the stomach and to prevent the
retrograde flow of gastric contents.
• Transport is achieved by peristaltic
contractions and relaxation of the
esophageal sphincters (upper and lower),
usually controlled by reflexes and by the
autonomic nervous system.
• In humans the esophagus is covered by
nonkeratinized stratified squamous
epithelium.
• In general, it has the same layers as the
rest of the digestive tract. In the submucosa
are groups of small mucus-secreting
glands, the esophageal glands, whose
secretion facilitates the transport of
foodstuffs and protects the mucosa.
21. • In the lamina propria of the region
near the stomach are groups of
glands, the esophageal cardiac
glands, that also secrete mucus.
• At the distal end of the esophagus,
the muscular layer consists of only
smooth muscle cells that, close to
the stomach, form the lower
esophageal sphincter; in the mid
portion, a mixture of striated and
smooth muscle cells; and at the Layers of Esophageal
proximal end, only striated muscle Wall:
1. Mucosa
cells. 2. Submucosa
3. Muscularis
4. Adventitia
• Only that portion of the esophagus 5. Striated muscle
6. Striated and smooth
that is in the peritoneal cavity is 7. Smooth muscle
covered by serosa. The rest is 8. Lamina muscularis
mucosae
covered by a layer of connective 9. Esophageal glands
tissue, the adventitia, that blends into
the surrounding tissue.
22. Histological Structure.
The esophagus has four coats:
an external or fibrous coat
a muscular coat
a submucous or areolar coat
and an internal or mucous coat.
The muscular coat (tunica muscularis)
isble thickness:
an external of longitudinal and an
internal of circular fibers.
The muscular fibers in the upper
part of the esophagus are a red
color, and consist chiefly of the
striped variety; but below they
consist for the most part of
involuntary fibers.
23. Section of the human esophagus. The
section is transverse and from near the
middle of the gullet.
a. Fibrous covering.
b. Divided fibers of
longitudinal muscular coat.
c. Transverse muscular fibers.
d. Submucous or areolar layer.
e. Muscularis mucosæ.
f. Mucous membrane, with
vessels and part of a lymphoid
nodule.
g. Stratified epithelial lining.
h. Mucous gland.
i. Gland duct
24. • The oesophagus has a stratified
squamous epithelial lining (SE)
which protects the oesophagus
from trauma;
• the submucosa (SM) secretes
mucus from mucous glands
(MG).
• The lumen of the oesophagus
is surrounded by layers of
muscle (M)
25. • ESOPHAGUS
Stained with H&E
1 - tunica mucosa
2 - tunica submucosa
3 - tunica muscularis propria
5 - epithelium of the mucosa
6 - lamina propria of the
mucosa
9 - glands in the submucosa
26. • ESOPHAGUS
Stained with H&E
1 - tunica mucosa
2 - tunica submucosa
3 - tunica muscularis
4- tunica adventitia
5 - epithelium of the mucosa
6 - lamina propria of the
mucosa
7 - muscularis mucosae
8 - glands in the lamina propria
27. • ESOPHAGUS
Stained with H&E
1 - tunica mucosa
2 - tunica submucosa
3 - tunica muscularis
propria
4 - tunica adventitia
5 - epithelium of the
mucosa
6 - lamina propria of the
mucosa
7 - muscularis mucosae
8 - glands in the lamina
propria
