Oral Mucous Membranes and Related Pathology Flashcards
what are the functions of mucous membranes
-absorption
-excretion
- protection
what are the 3 types of mucosa and describe each
-masticatory mucosa: keratinized
- lining mucosa:non-keratinized, thinner
- specialized mucosa: contains taste buds
where is masticatory mucosa located
gingiva and hard palate
where is lining mucosa located
-alveolar mucosa
-buccal mucosa
-floor of mouth
-ventral surface of tongue
- soft palate
what does the mucogingival junction separate
attached and unattached gingiva
where is the lining mucosa located in relation to the MGJ
above
where is the masticatory mucosa located in relation to the MGJ
below it
what is the free gingival groove
marked delineation between sulcular and junctional epithelium
what is the junctional epithelium
remnant of reduced enamel epithelium, base of pocket, typically from free gingival groove to tip of alveolar bone
what are you measuring when you measure pocket depth
depth of the sulcular epithelium, when probe hits bottom it hits top of junctional epithelium
where is submucosa found
in areas where you need salivary glands or fat layers
if theres no submucosa what do you see instead
mucoperiosteum
what is the mucoperiosteum
a periosteum with a mucosal surface with the periosteum of bone to form an apparent single layer
what are the zones that make up the submucosa of the hard palate
-gingival zone: attached gingiva
-fatty zone
- glandular zone: posterior, contains minor salivary glands
what are the epithelial layers from superficial-> deep
-stratum corneum: keratin layer
- stratum granulosum: granular cell layer
-stratum spinosum: spinous cell layer
- stratum basale: basal cell layer
describe the stratum corneum
cells are completely flat with no organelles, they are sacs of keratin proteinaceous mixture. high turnover rate, tend to exfoliate very easily
describe the stratum granulosum
flattened layer containing dense, dark granules. reduced but present organelles. contain keratohyaline granules
describe the stratum spinosum
characterized by round/ovoid cells. point of which desmosomes start to form
describe the stratum basale
single celled (cuboidal) layer near the bottom. these cells replicate and make cells for all of the other cell layers
what do epithelial rete pegs and connective tissue papilla do
aid in attachment in skin to the connective tissue layer
where are epithelial rete pegs located
they come down from the top
where are connective tissue papilla located
come up from the bottom
describe the characterisitics of epithelium
-rests on basement membrane
- exhibits one or more specialized intercellular attachments
-avascular
-cells are packed together
-may have polarity
what do epithelium receive all of their nutrients from since it is avascular
dermal connective tissue layer below the skin via diffusion
what are the variations of stratum corneum determined by
the way nuclei are organized or the way keratin is formed to determine the type of keratin present
what is orthokeratosis
refers to normal keratin formation with clinically normal presentation
what is parakeratosis
presence/retention of pyknotic nuclei in stratum corneum
what is hyperkeratosis
abnormal thickening of the stratum corneum. may exhibit abberant patterns of keratization
what is dyskeratosis
abnormal keratization below the level of stratum corneum (within stratum granulosum and/or stratum spinosum
what is gingival dyskeratosis
characterized by keratin pearls (below stratum corneum). these are pathognomic for sqaumous cell carcinoma
what are abnormalities related to the epithelial layer
-acanthosis
- acantholysis
- dysplasia
-leukoplakia
- inflammatory periodontal disease
what is acanthosis and where is it seen
hyperplasia of the epithelial layer (increase in cell number). typically seen in hands and feet
what is acantholysis
loss of intercellular attachments (desmosomes) between epithelial cells
what is metaplasia
a reversible change in which one adult cell type is replaced by another
what is dysplasia
a disorderly but non-neoplastic growth of tissue including the epithelial layer. characterized by pleomorphism, hyperchromatism, and loss of normal special orientation
what is leukoplakia
thickened epithelial layer. turns white when keratin gets wet
what happens to epithelium in periodontal disease
-calculus and susceptibility of hosts causes attachment loss
-results in apical migration of junctional epithelium
describe the location, morphology, and function of melanocytes
-located in basal cell layer
- dendritic morphology
-function: synthesis of melanin pigment granules
describe the location, morphology, and function of langerhans cells
-located in stratum spinosum
- dendritic morphology
-function: antigen trap in epithelium and transfers antigen infromation to CD4 lymphocytes
describe the location, morphology, and function of merkel’s cells
-located in basal cell layer
- rounded morphology and contain dense core granules
- function: unknown but something to do with tactile sensation of skin
describe the location, morphology and function of lymphocytes
-located in basal and spinous celll layers
- rounded morpholoy
- function: associated with immune and inflammatory responses. immune surveillance and antigen message processing. inflammation: both humoral and cellular response
what does the basement membrane consist of
basal lamina (made of lamina lucida and densa) and lamina reticularis (connective tissue)
-multiple layers of collagen that helps adhere CT to epidermal layer
-hemidesmosomes locking/connecting it to the basement membrane
what does lamina lucida in the basement membrane contain
-bullous pemphigoid antigen and type VII collagen
-Kalinin, K-laminin, entactin, epiligrin, BMG-1 and classic laminin
what does lamina densa in the basement membrane contain
-type IV collagen and type VII collagen
- fibronectin, integrins, BMG-1, and classic laminin
what does lamina reticularis in the basement membrane contain
-reticulin CT
- type 1 and type 2 collagen and elastin
what does the cytoplasm of the cell contain
-intermediate filaments or tonofilaments
-actin
-myosin
-talin
-vinculin
what do hemidesmosomes contain
-bullous pemphigoid antigen 1 and 2
-cadherins
-syndecans
- integrin alpha6 and beta4
what do cellular attachments do with trauma
work together to dissipate forces and help to absorb trauma and keep things from falling apart
what is common with cellular attachments in response to inflammation
loss of them
what are desmosomes
circular areas of attachment between cells. have tonofilaments that hook two cells together
what protein components in desmosomes help with adhesion
E-cadherin, P-cadherin, plakoglobin, periplakin, evoplakin, desmoplakin I and II
what are cadherins and wherre are they found
located in between desmosomes. they are a sticky protein that functions in allowing for communication to occur between cells
where are hemidesmosomes found and what are they
found along basement membrane. semi-circular areas that contain tonofilaments that attach cell down to basement membrane
what is a tight junction
area of two cells pressed together so tightly that there is a seal
what is a gap junction
small spaces in between the cells that allow for electrical communication
what are the permanent resident cell populations within lamina propria
-fibroblasts
-histocyte
-monocyte
-macrophage
- mast cell
- plasma cell
- endothelial cells
what do fibroblasts do
secrete collagen and elastin
what are histocytes
resident precursors of functional macrophages
what are monocytes
blood borne precursor of functional macrophage
-monocyte -> histocyte -> macrophage
what is a macrophage
phagocytic cell capable of antigen processing
what is a mast cell
secretes inflammatory mediators
what is a plasma cell
synthesis of immunoglobulins
what do endothelial cells line
blood and lymphatic vessels
what are the transient cell populations within lamina propria
neutrophil and lymphocyte
what are neutrophils
phagocytic cell capable of neutralizing antigens and killing bacteria
what are lymphocytes
humoral and cell-mediated immune response
