Lecture 10: Oral Mucosa Flashcards
the mouth is lined by a _______
moist mucous membrane
what two tissues compose the mucous membrane of the mouth?
- epithelium
- connective tissue (lamina propria & submucosa)(contains blood vessels and ducts from both major and minor salivary glands)
*there is also some lymphoid tissue
which tissue of the mouth functions more as a barrier for protection?
epithelium (antimicrobials)
*lamina propria fxns more for IMMUNE CELLS
the tissues of the mouth use what for protection?
beta-defensins
*cysteine rich, bind to negative charges on bacterial membranes and permealbilize
the oral mucosa is HIGHLY INNERVATED and contrasts from the pulp, dentin, and PDL bc it is capable of many more sensations. what are these sensations?
- Abeta: touch
- Adelta + C: pain & thermal
- Adelta: taste
all oral epithelium is what type of epithelium?
stratified squamous epithelium
*cell division occurs in deep layers and the superficial layers are sloughed off
does the oral mucosa have a fast or slow turnover time?
fast
- speeds healing
- leaves tissue more vulnerable to conditions that affect cell division like chema and radiotherapy
the volume of the oral EPITHELIUM is occupied by ____
cells
- keratinocytes are most numerous
- Non-keratinocytes: Merkel cells, melanocytes, langerhans
what are the 3 non-keratinocytes of the oral EPITHELIUM?
- merkel cells–sensory–basal layers
- melanocytes–pigment cells–basal layers (clear)
- langerhan cells–immune–SUPRA basal layers (clear)
*langerhan cells are more superficial than melanocytes, both are clear
from superficial to deep, what are the 4 layers of the keratinized epithelium vs the non-keratinized epithelium
keratinized: TOUGHER AND MORE IMPERMIABLE
- keratinized layer
- granular layer
- prickel cell layer
- basal cell layer
non-keratinized: MORE FLEXIBLE
- superficial layer
- intermediate layer
- prickel cell layer
- basal cell layer
all oral EPITHELIAL CELLS contain ______ which assemble into ______ providing cytoskeletal support (resist mechanical support w/o breaking
- cytokeratins
- intermediate filaments
- two major groups: type I (acidic) and type II (basic)
- different epithelial layers and tissues contain different cytokeratins
cytokeratins are the intracellular component of what?
desmosomes and hemidesmosomes
mutations in cytokeratins 5/14 (basal layer) leads to what?
epidermolysis bullosa simplex (EB simplex)
- rare, blistering in response to minor trauma
- most severe in epidermis but also oral consequences
mutations in cytokeratins 4 & 13 can produce regionally specific diseases such as ___
white sponge nevus
-affects oral non-keratinized epithelia
what are the fxns of cytokeratins in keratinized vs non-keratinized epithelium?
keratinized:
- promotes aggregation (tonofibrils)
- promote binding to another molecule (fillagrin)
non-keratinized:
- do not promote aggregation
- cannot complex with fillagrin
