ch 14 oral mucosa

dhyg 219

oral mucosa

stratified squamous epithelium > basement membrane > lamina propria

classifications of oral mucosa

lining mucosa, masticatory mucosa, specialized mucosa

lining mucosa

soft, moist, and stretchy surface that acts as a cushion for underlying structures

regions of lining mucosa

buccal, labial, alveolar, floor of mouth, ventral tongue, and soft palate

lining mucosa histology

non-keratinized stratified squamous epithelium

moveable base due to elastic fibers in lamina propria

fordyce spots- small, yellowish elevations correspond with sebaceous glands

masticatory mucosa

rubbery surface texture and resilient

regions of masticatory mucosa

attached gingiva, hard palate, and dorsal tongue surface

masticatory mucosa histology

keratinized stratified squamous epithelium

interface is highly interdigitated with numerous rete ridges

increased firmness of tissue because of rete ridges

specialized mucosa

region- dorsal tongue

associated with lingual papillae

histology- discrete structures of epithelium and lamina propria

epithelium of oral mucosa

nonkeratinized- lining, orthokeratinized- masticatory, parakeratinized- masticatory

nonkeratinized

most common type of epithelium in oral cavity

found in the most superficial layers of lining mucosa

nonkeratinized layers

basal layer- cuboidal epithelial cells, stratum basale

intermediate layer- stratum intermedium, larger staked polyhedral cells, makes up the bulk of epithelium

superficial layer- stratum superficiale, squames, larger polyhedral epithelial cells, shed and die with age (top layer)

orthokeratinized

least common in oral cavity

has keratinization in all layers

orthokeratinized layers

basal- stratum basale

prickle cell- makes up bulk of epithelium, has a prickly appearance

granular- contain keratohyaline granules

keratin-most superficial, variable thickness, anucleated

parakeratinized

believed to be an immature form of orthokeratinized epithelium

cells of the keratin layer in parakeratinized epithelium contain keratin and a nucleus, rather than just keratin.

hyperkeratinized

nonkeratinized epithelium transforms into a keratinizing type due to frictional or chemical trauma

linea alba, bruxism, maxillary tuberosity, retromolar pad

trauma= increase in keratin, heat from smoking, hot fluids

lamina propria

found deep to the basement membrane

main fiber group- collagen

papillary- most superficial layer

capillary plexus- found between papillary layer and deeper layers that provides nutrition for all mucosa

dense layer- deeper portion of lamina propria

submucosa- deep to the dense layer, may not be present

most common cell- fibroblast

labial and buccal mucosa

inner lips and cheeks

appearance- opaque pink, shiny, moist, may have melanin or fordyce spots

epithelium- thick, nonkeratinized

lamina propria- irregular and blunt connective tissue papillae, some elastic fibers, extensive vascular supply

submucosa- present with adipose tissue and minor salivary glands, firm attachment to muscle

alveolar mucosa

lines vestibule

appearance- reddish/pink, shiny, moist, very mobile

epithelium- thin, non-keratinized

lamina propria- connective tissue papillae sometimes absent, many elastic fibers, extensive vascular supply

submucosa- present in minor salivary glands and many elastic fibers, loose attachment to muscle or bone

floor of mouth and ventral tongue (lining mucosa)

appearance- reddish/pink, moist, shiny, compressible with vascular blue areas, mobility varies

epithelium- very thin, nonkeratinized

lamina propria- extensive vascular supply, mouth floor- broad connective tissue papillae, ventral tongue- numerous connective tissue papillae with some elastic fibers and minor salivary glands

submucosa- mouth floor- adipose tissue with submandibular and sublingual glands, loosely attached, ventral tongue, very thin and firmly attached

soft palate (lining mucosa)

appearance- deep pink with a yellow hue and moist surface, compressible and very elastic

epithelium- thin, nonkeratinized

lamina propria- think lamina propria with numerous connective tissue papillae and distinct elastic layer

submucosa- very thin with adipose tissue and minor salivary glands, firm attachment

attached gingiva (masticatory mucosa)

appearance- opaque pink, dull, firm, immobile, melanin and stippling possible

epithelium- thick keratinized (mainly para, some ortho)

lamina propria- tall, narrow connective tissue papillae, very vascular, serves as mucoperiosteum to bone

submucosa- NOT present

hard palate (masticatory mucosa)

appearance- pink, immobile and firm medial portion, contains rugae and raphe, cushioned later portions

epithelium- thick orthokeratinized

lamina propria- medial portion rugae and raphe serve as mucoperiosteum

submucosa- present only in lateral portions, adipose tissue in anterior and minor salivary glands in posterior

goal of grafting

increase the amount of keratinzied atttached gingiva

renewal rate, the oral mucosa

higher tissue renewal rate for oral mucosa than skin

traumatic lesion should heal completey in 2 weeks

if there is a suspicious lesion ahve patient return in two weeks, if still present refer for a biopsy

do not wait until next recall, may grow or metastasize if malignant

buccal and labial mucosa renewal rate

10-14 days

attached gingiva renewal rate

10 days

taste buds renewal rate

10 days

junctional epithelium renewal rate

4-6 days found in sulcus