Mucous membranes Flashcards by asw asw

mucous membranes are composed of what 2 tissues?

1) epithelium

2) lamina propria (and sometimes submucosa)

How well did you know this?

Not at all

Perfectly

what type of immune cells can the oral epithelium produce?

beta-definsins

How well did you know this?

Not at all

Perfectly

what are the functions of the oral mucosa?

proteciton
ingestion
sensory

How well did you know this?

Not at all

Perfectly

what type of nerve fibers do Dentin & pulp contain? what do these mainly sense?

C, A-delta, A-beta

all sense (mostly) pain

How well did you know this?

Not at all

Perfectly

what types of nerve fibers are found in the PDL?

C & A-delta: pain sensation

A-beta fibers: proprioceptive

How well did you know this?

Not at all

Perfectly

oral mucosal nerve fibers: what types are present, and what do they sense

A-beta: touch

A-delta and C fibers: pain

A-delta and C fibers: thermal

A-delta: taste

How well did you know this?

Not at all

Perfectly

what types of tissues can make up the “connective tissue” of oral mucosa?

lamina propria

- submucosa

How well did you know this?

Not at all

Perfectly

all oral epithelium is made of _____________ epithelium

stratified squamous epithelium

How well did you know this?

Not at all

Perfectly

where are the self-renewing cells of oral epithelium found?

deep layers

How well did you know this?

Not at all

Perfectly

what is the fate of the superficial oral epithelium layers?

migrate, mature & slough off at the surface

How well did you know this?

Not at all

Perfectly

T/F: the turnover rate for gingival epithelium is faster than junctional epithelium and taste buds

FALSE-

Gingiva= 41-57 days

junctional epithelium= 5-10 days

taste buds= 10 days

How well did you know this?

Not at all

Perfectly

what are some of the conditions that result from head/neck radiotherapy?

1) diffuse mucositis/ulcer

2) extensive ulceration

How well did you know this?

Not at all

Perfectly

_________ cells are the most numerous cell type in the oral epithelium

keratinocytes

How well did you know this?

Not at all

Perfectly

what are the non-keratinocyte cells of the oral epithelium?

A) melanocytes- pigment- basal layers

B) langerhans (dendritic) cells- immune- supra-basal layer

C) merkel cells- sensory- basal layer

How well did you know this?

Not at all

Perfectly

“clear” cells dramatically revealed by a lack of _________ staining

cytokeratin

How well did you know this?

Not at all

Perfectly

Melanocytes are found in the _______ layer, and contain pigment packed ________

found in basal layer

contain melanosomes (contain melanin)

How well did you know this?

Not at all

Perfectly

Langerhan’s cells have a similar appearance to __________, but are found in what layer?

similar to melanocytes (in appearance)

found in ***suprabasal layers

How well did you know this?

Not at all

Perfectly

what characteristics do keratinized and non-keratinized epithelium share?

both have basal layer (cell division) and a prickle cell layer (appearance caused by DESMOSOMES)

How well did you know this?

Not at all

Perfectly

which layer is distinct between keratinized and non-keratinized epithelium? what are the differences?

Superficial layers are different
Keratinized has GRANULAR layer, no organelles, dehydrated and is tougher
non-keratinized has INTERMEDIATE layer, organelles and is flexible

How well did you know this?

Not at all

Perfectly

all keratinocytes contain ________

cytokeratins

How well did you know this?

Not at all

Perfectly

what do cytokeratins assemble into? what is their role?

intermediate filaments- provide skeletal support

How well did you know this?

Not at all

Perfectly

what are the 2 major groups of intermediate filaments?

Type 1- acidic

Type 2- basic

How well did you know this?

Not at all

Perfectly

T/F: each epithelial cell produces at least 2 cytokeratins- one of each type

true (at lease 1 acidic & 1 basic)

How well did you know this?

Not at all

Perfectly

intermediate filaments are the strongest ________ elements

cytoskeletal

How well did you know this?

Not at all

Perfectly

cytokeratins also form the intracellular components of ________ and ________

desmosomes & hemidesmosomes

Microfilaments are more _______, while microtubules are more ______

microfilaments= rigid microtubules= flexible

mutations in cytokeratins 5/14 leads to what disorder?

Epidermolysis bullosa simplex (EB simplex)

what layer of oral epithelium does EB simplex effect?

basal layer

T/F: different epithelial layers contain characteristic cytokeratins

true

mutations in cytokeratin genes can produce regionally-specific disease, such as ________

white sponge nevus - autosomal DOMINANT disorder - affects oral non-keratinized epithelium - soft, white, spongy plaques form

____________ epithelium is tougher, and less permeable (more impermeable)

keratinized

cytokeratin in keratinized epithelium has fibers that come together into _______

tonofibrils | -shows up as granules (not seen in non-keratinized)

tonofibrils promote _______, while ________ permits binding with fillagrin

tonofibrils- aggregation keratohyalin granules- binding w/ fillagrin

membrane coating granules are maembrane-bound organelles filled with what?

glycolipids

where do membrane coating granules first appear? where are they released?

1st appear- upper prickle cell layer release in more superficial layers to coat cell

in what type of epithelium are membrane coating granules found?

occur in BOTH keratinized & non-keratinized epithelia

what is the function of membrane coating granules? what does the difference in chemical composition create?

function= serve as an INTERcellular (between cells) barrier to aqueous substances different chem composition causes a more effective barrier in keratinized epithelium

membrane thickening is caused by the inner face of keratinocytes in upper layers of what?

both non-keratinized & keratinized epithelium

where is membrane thickening much more pronounced? what causes this?

more pronounced in keratinized epithelium -cornified envelope in keratinized epi

what is the cornfield envelope?

a cross-linked protein sheath -made of LORICRIN & other proteins (membrane thickening)

differences in membrane thickening causes a greater _______________ in keratinized epithelium

greater effective paracellular permeability barrier

keratinohyalin granules appear as what?

dark stained cells near surface of keratinized epithelium -these are filled with fillagrin

parakeratinized gingiva still has _______ in its superficial layer

nuclei

what is parakeratinized gingiva associated with?

inflamed gingiva

most of the volume of the lamina propria is occupied by _________

ECM | extracellular matrix

what types of cells are present in the lamina propria?

fibroblasts, macrophages, mast cells, other inflammatory cels

what is the extracellular matrix (ECM) of the lamina propria made of?

A) ELASTIN B) colagen (types 1 & 3) C) gylycoproteins (fibronectin)

the relative amount of types 1 to type 3 collagen is greater for ________ regions of the oral cavity

less flexible

hard tissues contain _______ collagen, while softer tissues contain more ______ collagen

rigid/hard= type 1 soft/loose= type 3

elastin is more prominent in oral mucosa than in _____ or _____

pulp or PDL

the basal lamina is convoluted, leading to what structures?

rete pegs (epithelium) and connective tissue papillae (lamina propria/connective tissue)

what are the 2 layers of the lamina propria?

papillary layer reticular layer

long, thin rate pegs are often found in the ______

gingiva

what causes "Stippling" of the gingiva?

underlying rete pegs and connective tissue papillae

what does the submucosa contain? what does it separate?

- contains larger blood vessels & nerves that supply LP - glands -separates lamina propria from bone & muscle

give examples of mucoperiosteum

- gingiva - hard palate next to gingiva - rugae region - median raphe

what are the 3 specializations of the oral mucosa

1) lining 2) masticatory 3) specialized

lining mucosa: characteristics

- non-keratinized epithelium - lamina propria has fewer collagen fibers, more elastic fibers - submucosa usually present - short, broad connective tissue papillae & rate pegs

what are the 3 regions of the lip?

exterior skin, vermillion zone, labial mucosa

exterior skin of lip region:

- keratinized - thinnest of lip epithelium - sweat glands & hair follicles

vermillion zone of lip:

- keratinized - thin - blood vessels close to surface - NO sweat or mucous glands

labial mucosa of lip

- non keratinized - thicker - mucous glands

masticatory mucosa: overview

-keratinized (or parakeratinized during inflammation) - dense lamina propria…. more collagen fibers - many long, thin connective tissue papillae - submucosa A) variably present in hard palate B) not in gingiva- mucoperiosteum (more rigid)

sulcar epithelium:

part of free gingiva which faces tooth generally non-keratinized

Junctional epithelium:

- forms SEAL WITH HARD TOOTH TISSUE - oriented along long axis of tooth - HIGHLY PERMEABLE - 2 basal lamina

what are the 2 basal lamina of junctional epithelium?

1) external- JE/lamina propria | 2) internal- JE/tooth

what makes up the anchoring fibrils of the basal lamina of junctional epithelium?

type 7 collagen linking to a network of type 4 collagen

what is missing in the internal basal lamina of the junctional epithelium that is present in the external BL?

Internal BL lacks collagen components

in junctional epithelium, collagen components of the basal lamina provide direct connection to what?

collagen of lamina propria (lamina densa & anchoring fibril of BL) (collagen fibrils of LP)

what is the origin of junctional epithelium?

Reduced enamel epithelium

T/F: due to its specialized nature, junctional epithelium cannot regenerate rapidly

False can regenerate rapidly will occur around dental implants

what is the vascular supply of the gingiva?

superior alveolar palatine inverior alveolar buccal, mental, sublingual all supply PDL, interdental septa, oral mucosa which can supply the gingiva