2. The oral mucosa is the mucous membrane lining the
inside of the mouth and consists of stratified squamous
epithelium termed oral epithelium and an underlying
connective tissue termed lamina propria.[
Lapisan yang melapisi bagian dalam mulut yang dilapisi
oleh epitel pipih berlapis yang dibawahnya terdiri dari
jaringan ikat dan lamina propria
3. The two main tissue components of the OM are:
• The oral epithelium, it is a stratified squamous epithelium
• The lamina propria, it is the underlying connective tissue.
The interface between oral epithelium and lamina propria
(basement membrane) is usually irregular and the so
called connective tissue papillae interdigitate with the
epithelial ridges.
4. The tissue component under the
oral mucosa is the submucosa
and it is less easy to recognize
the junction between them than
between oral epithelium and
lamina propria.
5. •
It is derived from the embryonic ectoderm and forms the
primary barrier between oral environment and underlying
tissues.
6. • It consists of stratified
squamous cells
arranged in 4 distinct
layers
• A=stratum
germinativum (basal
layer);
• B=stratum spinosum
(prickle cell layer);
• C=stratum granulosum
(granular layer);
• D=stratum corneum
(keratinised or cornified
layer)
7. It maintains its continuity by a continuous cell renewal:
• Cell proliferation : dilakukan oleh proliferasi sel
• Cell maturation : setelah proliferasi lalu melakukan
maturasi untuk membentuk lapisan paling atas
Selalu mempertahankan continuitas atau memperbaharui diri melalui
: Maturasi dan proliferasi
The cells of oral epithelium that take part in the renewal are:
• Progenitor cells: the function is to divide and provide
new cells
• Maturing cells: they undergo a process of maturation to
form the protective cell layer.
8. The progenitor cells are located in the basement membrane
in thin epithelia (floor of the mouth) and in the lower two
to three cell layers in thicker epithelia (cheek)
Progenitor cells divide into new progenitor cells or into
maturing cells.
Letaknya di atas membrana basalis, terletak pada lapisan
sel basal, sel pada stratum basal menunjukkan aktivitas
mitosik paling tinggi, cenderung berkelompok.
9. • The cells of the st. basale shows the highest mitotic activity.
• This maturation results in keratinization or non-keratinization
• These basal cells tend to cluster and are more frequently found at the
bottom of the retes of the epithelium
10. Basal layer or stratum germinativum
•
•
•
•
•
•
•
inner most layer
cuboidal or columnar cells
in the thin mucosa of the floor
of the mouth = 1 layer
Pada mukosa yang tipis = hanya
1 lapis sel basal
in the cheeks and palate = 2 or 3
layers (pada pipi atau palatum,
bisa 2 atau 3 lapis)
also called stratum basale
because it attaches firmly to the
basal lamina of the basement
membrane (disebut stratum
basal karna melekat pada lamina
basal pada dasar membran.
contain progenitor or stem cells
= produce the basal cells that
mature into all cells of the
epithelium
11. Diagram depicting the compartments of the oral epithelium and indicating the
statistical basis of a homeostatic system, that is, after mitosis one cell remains in the
reproductive compartment while the other moves into the functional compartment.
A. Ian Hamilton And H. J. J. Blackwood J. Anat. (1974), 117, 2, Pp. 313-327
12. Di epitel ga ada pembuluh darah ya, jadi pembuluh
darah itu di lamina propria jadi metabolisme nya
berasal dari lamina propria. Stratum basal itu =
reproductive compartment sedangkan yang stratum
di atasnya itu = functional compartment
13. Epithelium of the cheek showing the constituent cell layers and compartments.
A. Ian Hamilton And H. J. J. Blackwood J. Anat. (1974), 117, 2, Pp. 313-327
14. prickle layer = stratum spinosum
• Lies above the first one and contains several
rows of elliptical or spherical cells.
• Di superfisial stratum basal, terdiri dari
beberapa lapisan
• from maturation and migration of basal cells
• several layers thick
• Both, st. basale and st. spinosum, together
constitute half to two third of the thickness of
the oral epithelium. (1/2 -2/3)
• The cells have cytoplasmatic processes that
have contact with other processes of other
cells. connected by bundles of intermediate
filaments
melanocytes are common
• Langerhans cells also found – in the more
superficial layers of the prickle layer
• Sel-sel memiliki proses cytoplasmatic
yang memiliki kontak dengan proses lain
dari sel-sel lain. dihubungkan dengan
bundel filamen menengah melanosit
yang umum. Sel Langerhans juga
ditemukan - di lapisan lebih dangkal dari
lapisan merinding
15. As cells leave the basal layer and enter into
differentiation, they become larger and
begin to flatten and accumulate
cytoplasmic protein filaments,
representing the cytokeratins. Terdapat
akumulasi filamen sitoplasmic yang
merupakan representasi sitokeratin.
As the cells enter the prickle cell layer,
small organelles known as membranecoating granules representing
accumulating lipid become evident . Trus
ada granula yang melapisi membran dan
mengandung lipid
In addition to the accumulation of lipids
and keratins, the differentiating
keratinocytes synthesize and retain a
number of specific proteins, including
profilaggrin, involucrin, and other
precursors of the thickening of the cell
envelope .
16. granular layer = stratum granulosum
•
•
•
•
•
•
•
•
The granular layer - stratum granulosum is the next layer and consists of larger
flattened cells containing small granules.
Lebih memipih dan ada granula yang lebih
kecil lagi.
made up of epithelial cells displaced from
the prickle
in keratinized epithelium – cell synthesize
large quantities of proteins (including
keratin) – cytoplasm appears granular
the granules = keratohyalin granules
these granules surround the keratin
filaments as they develop
as keratin is made – cells become thinner
and flatter
the plasma membrane thickens and
becomes less permeable
(plasma
membran akan menebal dan kurang
permeable)
the cells then die and dehydrate creating
bundles of keratin surrounded by
keratohyalin sandwiched between two
phospholipid membranes. sel kemudian mati
dan dehidrasi menciptakan bundel keratin
dikelilingi oleh keratohyalin terjepit di antara
dua membran fosfolipid
17. keratinized layer/superficial layer = stratum corneum
Differentiation in keratinized
epithelia leads to production
of the stratum corneum.
The cornified cells making up
this layer are flat and
hexagonal in shape, filled with
a compact array of condensed
cytokeratin filaments, bounded
by a thickened cell envelope,
and surrounded by an external
lipid matrix.
18. keratinized layer/superficial layer = stratum corneum
At the boundary between the granular and cornified
layers, the membrane-coating granules migrate to
the superficial (apical) aspect of the keratinocyte,
where the bounding membrane of the organelle
fuses with the cell plasma membrane so that the
lipid lamellae are extruded into the extracellular
spaces of the surface layer . Thus, the membranecoating granules are believed to be responsible for
the formation of a superficial, intercellular,
permeability barrier in stratified squamous
epithelium.
After the granules are extruded, the interior of the
cell becomes filled with aggregated cytokeratin
filaments, and involucrin, loricrin, and other
proteins are deposited on the inner aspect of the
plasma membrane as a thick band of protein that
becomes covalently cross-linked.
Dengan demikian, granul membran-lapisan yang
diyakini bertanggung jawab untuk pembentukan
dangkal, antarsel, permeabilitas barrier epitel
skuamosa berlapis.
Setelah butiran yang diekstrusi, bagian dalam sel
menjadi penuh dengan filamen cytokeratin agregat,
dan involucrin, loricrin, dan protein lain yang
disimpan pada aspek dalam dari membran plasma
sebagai band tebal protein yang menjadi kovalen
cross-linked.
19. Pada stratum granulosum ada granula keratohyalin,
kalau ada diferensiasi akan bergerak ke superfisial,
lalu akan berikatan pada membran dan organela
kemudian berfusi sehingga keratinnya ini akan
bewarna, granula yang berisi lipid juga akan
dikeluarkan pada lapisan keratin.
20. Cells that are driven from progenitor cells and ready for
maturation passes the entire epithelium to form the
protective layer.
Sel yang didorong dari sel progenitor dan siap untuk
pematangan melewati seluruh epitel membentuk
lapisan pelindung.
In general maturation in the oral cavity follows two main
patterns:
• Keratinization
• Nonkeratinization
• Parakeratinization pada kulit terjadi hanya
pada kondisi inflamasi tapi di mulut bisa pas
normal
21. Keratinization or cornification is the formation of a
surface of keratin. pembentukan keratin
Such process is seen in the oral mucosa of the palate,
gingiva and in some regions of the tongue dorsum.
A keratinized epithelium shows in histological sections
a number of layers (strata)
22. Nonkeratinization occurs in regions with less mechanical
influences to the OM, such as cheek, lips, underside of
the tongue and the soft palate.
Nonkeratinized epithelium is usually thicker than
keratinized epithelium.
No sudden changes in the cells above the st. spinosum
occur in nonkeratinized epithelium
23. In so called parakeratinized mucosa, such as parts of the
hard palate and the gingiva, in the surface layer the nuclei
are shrunken and retained in many or all squames. Also
keratohyaline granules are present in this layer. Masih
ditemukan nukleus
Such phenomenon is a normal event in the oral epithelium,
but not true for the epidermis, where p arakeratinization is
associated with diseases such as psoriasis.
24. keratinized layer/superficial layer = stratum corneum
• in the masticatory mucosa - large amounts of keratin are
present >> so the outermost layer = keratinized layer
• BUT in the lining mucosa – no keratin is made – this layer is
called the superficial layer
• presence of keratin prevents growth of microorganisms and
physical damage
• covered in secretions from glands to provide some moisture
• cells are flattened = squames
• keratinized layers – cells do not contain nuclei
• pattern of keratinization in these cells = orthokeratinization
• a variation in keratinization is seen in the mucosa of parts of
the hard palate and much of the gingiva = parakeratinized
mucosa
• only the cells in the surface stain for keratin and the nuclei are
retained in many or all of the squames + fewer keratohyaline
granules in the underlying granular layer (immature form of
orthokeratinization)
• in the skin – parakeratinization is a disease state (e.g.
psoriasis)
•
– normal in oral mucosa
• the keratinized mucosa of the oral cavity – 20 cell layers thick
-can be thicker than the palms and soles!!!!
25. keratinizing vs non keratinizing epithelia
In nonkeratinizing epithelia, the accumulation of lipids and of
cytokeratins in the keratinocytes is less evident and the change in
morphology is far less marked than in keratinizing epithelia. (pada
nonkeratinisasi akumulasi lipid dan keratin kurang dan perubahan
morfologi kurang sedangkan pada yang keratinisasi jelas)
The mature cells in the outer portion of nonkeratinized epithelia
become large and flat and possess a cross-linked protein envelope,
but they retain nuclei and other organelles, and the cytokeratins do
not aggregate to form bundles of filaments, as seen in keratinizing
epithelia. ( sel yang matur pada permukaan luar dari epitel
nonkeratinisasi terlihat lebih besar dan pipih tapi masih
mempertahankan nukleusnya)
28. Orthokeratinization of stratified squamous epithelium may occur at sites
in the oral cavity where the mucosa is subjected to habitual mechanical
stress - such as continuous trauma from chewing. Note the stratum
corneum (A). No nuclei are visible in contrast with the parakeratinized
variety.
Lapisan epitel yang mengalami keratinisai juga disebut sebagai
orthokeratinisasi. PadaTerjadi pada rongga mulut dimana mukosanya
mendapat tekanan mekanis, misalnya pada gingiva, tidak ada
nukleusnya lagi.
29. The mucosa covering the hard palate exhibits a distinct keratinized layer
-High connective tissue papillae are associated with keratinized
epithelium.
-This form of keratinization in the oral cavity is referred to as
orthokeratinized stratified squamous epithelium.
30. This is a section of labial mucosa.
The epithelium (B) is non-keratinized stratified squamous.
Examine the uppermost layer (*) carefully and note that these cells
still exhibit nuclei. The loose connective tissue of the lamina propria
that underlies the epithelium inserts up into this overlying layer in
finger-like projections or papillae (A). -the non-keratinized epithelium
is very thick
31. Parakeratinized epithelium of gingiva.
Note the connective tissue papillae (A). The overlying epithelium is
keratinized
There is the absence of a distinctive stratum granulosum and the
presence of nuclei (*) in the outermost layers (absent in a stratum
corneum). Tapi piknotik
32. - dorsum of the adult tongue.
- The majority of the tiny projections in this image
are filiform papillae (A).
- They are exposed to constant abrasive action
during eating, talking, swallowing, etc. This results
in their tips becoming protected by a layer of
keratin.
- A buildup of keratin can result in their elongation
– has a hairy appearance = hairy tongue
This is the histological
appearance of filiform
papillae. Keratinization
(A) occurs on the tips of
these papillae. Each
papilla has a core of
connective tissue (B).
33. Histologic sections of three types of lingual
papillae.
A, Several filiform papillae and a fungiform
papilla from the anterior part of the tongue. The
epithelium of the filiform papillae is keratinized;
that of the fungiform papilla is keratinized thinly
or nonkeratinized.
B, Section through the foliate papilla. The
nonkeratinized epithelium covering the papilla
contains numerous taste buds (arrowheads)
situated laterally.
C, Histologic section of taste buds in the epithelium
of circumvallate papilla
A deep groove runs around the papilla, and the
glands of Ebner empty into it.
Inset: Enlarged view of a simple taste bud with its
barrel-like appearance and the apical pore
(arrowhead).
34. The concept of epithelial homeostasis implies that cell
production in the deeper layers will be balanced by loss of cells
from the surface
The turnover time is the period of time is needed by a cell
to divide and pass through the entire epithelium. Periode
yang dibutuhkan sel untuk membelah dan mengalami
maturasi sampe pada lapisan superfisial
The turnover time is 52 to 75 days in skin, 41 to 57 days in
the gingiva and 25 days in the cheek.
Homeostasis dari epitel, ada keseimbangan antara sel
basalis dengan sel yang mengelupas.
35. Mitotic activity affected by a number of factors, such as time of
day, stress, and inflammation. For example, the presence of a
slight subepithelial inflammatory cell infiltrate stimulates mitosis,
while severe inflammation causes a marked reduction in
proliferative activity. Aktivitas mitosis dipengaruhi oleh beberapa
faktor seprti waktu, hari, stres dan imflamasi. Inflamasi yang
ringan menstimulasi mitosis, kalau berat mempengaruhi aktivitas
proliferasi.
After cell division, each daughter cell either recycles in the
progenitor population or enters the maturing compartment. The
switch between proliferation and differentiation is modulated by
the presence of factors, such as extracellular calcium, phorbol
esters, retinoic acid, and vitamin D3 . Maturasi di pengaruhi oleh
kalsium , phorbol ester, retinoid acid dan vitamin d3
36. Melanocytes – basal layer – menghasilkan melanosit-warna
Merkel cells - basal layer- sel yang saraf
- is a sensory cell responding to touch
Langerhans’ cells –fungsi imunologi, mampu untuk mengenali
material yang masuk dan memperkenalkan ke limfosit T
– they can move in and out of the epithelium
- They have an immunologic function, recognizing &
processing antigenic material that enters the epithelium from the
external environment and presenting it to helper T lymphocytes.
Inflammatory cells -- limfosit –T dan B (B—plasma--antibodi)
- mostly lymphocytes >>pmn (pada keadaan normal biasanya
limfosit lebih sering dari pmn)
They do not participate in the process of maturation
38. A
B
B. Preparat lapisan superficial oral epithelium
menggambarkan sel Langerhans cells (panah)
(ATPase)
39. keratinocytes produce interleukins (1, 6, 7, 8, 10, 11, and 12), colony-
stimulating factors (GM, G, and M), and tumor necrosis factor-, all of
which modulate the function of Langerhans’ cells.
In turn, Langerhans’ cells produce IL-1, which can activate T
lymphocytes, which secrete IL-2, thus bringing about proliferation of
T cells capable of responding to antigenic challenge.
IL-1 also increases the number of receptors to melanocyte-stimulating
hormone in melanocytes and so can affect pigmentation.
The influence of keratinocytes extends to the adjacent connective
tissue where cytokines produced in the epithelium can influence
fibroblast growth and the formation of fibrils and matrix.