Oral mucosa Flashcards
functions of oral mucosa
protection
sensation
thermal regulation
secretions
2 parts of oral cavity
vestibule bounded by lips and cheeks
and oral cavity which is separated from the vestibule by alveolar bone and gingiva
types of oral mucosa
lining
masticatory
specialized
% of each type of mucosa
60% IS Lining
25% Masticatory
15% specialized
the coloration depends on
the number of vessels and their dilation in underlying connective tissue
amount of melanin pigment present
degree of keratinization
thickness of epithelium
sebaceous glands are found in?
upper lip, buccal mucosa and in about 3 quarters of adults in masticatory mucosa and dorsum of the tongue
sebaceous appear as yellow spot known as
Fordyce’s spot
what present on the dorsum of the tongue and hard palate
papillae and transverse ridges (Rugae) respectively
two main tissues of oral mucosa
stratified squamous epithelium
and lamina propria (underlying connective tissues)
what separates the oral mucosa from the underlying muscle or bone in lips cheeks hard palate
a lose fatty or glandular connective tissue containing major blood vessels and nerves
mucoperiosteum
the oral mucosa such as gingiva and hard palate is directly attached to periosteum known as
waldeyers ring
largest accumulation of lymphoid tissues are found in posterior part of oral cavity
(lingual, palatine and pharyngeal)
2 Functional populations of epithelium cells of oral mucosa
progenitor population (that divide and provide new cells) maturating population ( that continually mature and differentiate)
cell turnover
the time taken for a cell to divide and pass though the entire epithelium is known as turnover rate
skin turnover time
52 to 75 days
gut turn over time
4 to 14 days
gingiva turn over time
41 to 57 days
cheek turn over time
25
turn over rate is faster in
non keratinized epithelium such as the buccal mucosa rather than the gingiva
keratinized epithelium what type of mucosa
masticatory and specialisez
where is keratinized epithelium present
hard palate, gingiva, dorsum of the tongue
each layer in keratinized epithelium and the shape of their cells
- stratum basale ( cuboidal or low columnar)
- stratum spinosum or prickle cell layer (elliptical or spherical cells)
- stratum granulosam ( flattened cells)
- startum corneum ( flat squamous cells) no nuclei
ortho keratnized
startum corneum with no nuclei
para keratinized
a variation of keratinized layer in which startum corneum have flattened nuclei called pyknotic nuclei
why startum spinosum have prickled cells reason?
in histological preparatuon their cells shrink away remaining in contact with other cells through desmosomes.
startum granulosum stains?
intensely with acid dyes ( hematoxylin) basophilic
stratum granulosum contains?
granules called keratohyalin granules
startum corneum stains
dark pink with eosin
non keratinized epithelium is present in what mucosa
lining mucosa
lining mucosa is present in
lips, buccal mucosa, alveolar mucosa, soft palate underside of the tongue, soft palate and floor of the mouth
layers or non keratinized
first 2 layers are different
stratum intermedium in place of stratum granulosum and stratum superficiale
clinical significance of turnover
the drugs target the cell in CANCER patients which have a high rate of turnover like the cells of hair and nails
keratinocyte with small molecular weight
40kDa found in glandular and simple epithelium
keratinocyte with intermediate molecular weight
found stratified epithelia
keratinocyte with high molecular weight
65Kda is found in stratified keratinized epithelium
non keratinocytes cell in oral epithelium
melanocytes
langerhans cells
lymphocyte
Merkels cell
location of each type of non keratinized cell
melanocyte is present in basal layer para basal
langerhans are present in supra basal
merkel cell is present in basal layer
and lymphocytes are variable
what are the only non dentritic non keratinocytes ?
merkels cells
what cells have desmosomes for attahcment of adjacent cells
merkels cells
where melanin pigment is most seen
gingiva, hard palate, tongue buccal mucosa
causes of high activity of melanocytes
smoking
genetically
drugs
high cortisone level
melanin is synthesized within melanocytes as small structures called as
melanosomes
person with heavy melanin pigment the cell containing melanin may be seen in
connective tissue which are usually macrophages that take up the melanosomes and are called melanophages
one special characterstic about langerhan cells
rod shaped granule or tennis racket shaped granules which are called BIRBECK GRANULE
langerhans cells are made in
bone marrow
mucogingival junction
junction between attached gingiva and alveolar mucosa
epithelium of attached and alveolar mucosa
attached gingiva has keratinized masticatory mucosa
alveolar mucosa has non keratinized lining epithelium
space between tooth and gingiva and clinical significance
gingival sulcus (contains tartar and bacteria)
what is present between free gingiva and attached gingiva
free gingival grove
junctional epithelium
bewteen attached gingiva and tooth
col
same as junctional epithelium and Replaced gradually by diving cell making more depression. interdental papillae have an outline of col
non keratinized
when the lingual frenum is short its called
Ankyloglossia (frenectomy)
linea alba
whitish ridge on the buccal mucosa at the occlusal plane of the teeth which is keratinized
