Histology 7: oral mucosa

Oral Mucosa

The lining of the oral cavity, composed of various types of epithelium, including lining, masticatory, and specialized mucosa.

Stratified Squamous Epithelium

A type of epithelial tissue characterized by multiple layers of cells, providing protection in areas such as the oral cavity.

Lining Mucosa

The type of oral mucosa that covers areas like the floor of the mouth and cheeks, typically nonkeratinized and flexible.

Masticatory Mucosa

Oral mucosa that is keratinized and withstands the mechanical stress of chewing, located in areas like the hard palate.

Specialized Mucosa

Mucosa found on the surface of the tongue, containing papillae that have specialized functions such as taste.

Lamina Propria

The connective tissue layer beneath the epithelium, composed of papillary and reticular layers, providing support and nourishment.

Seromucous Glands

Glands that produce both serous (watery) and mucous (viscous) secretions, found in various locations in the oral cavity.

Vermilion Border

The red margin of the lips where the nonkeratinized mucosa meets the skin.

Keratinization

The process by which cells in the epidermis become filled with keratin and move upwards to form a tough, protective layer.

Free Gingival Groove

The groove that separates the free gingiva from the attached gingiva.

Dentogingival Epithelium

The epithelium that lines the sulcus and connects the gingiva to the tooth surface.

Parakeratin

A form of keratinized epithelium where nuclei are retained in the keratin layer.

Orthokeratin

A type of keratinized epithelium that lacks nuclei in the keratin layer.

Gingival Sulcus

The space between the tooth and the free gingiva, where plaque and bacteria can accumulate.

Periodontal Disease

An inflammatory disease affecting the tissues surrounding the teeth, which can lead to apical migration of gingiva.

Keratinized Mucosa

Mucosa that is covered with a layer of keratin, providing a barrier to protect underlying tissues.

Nonkeratinized Mucosa

Mucosa that does not have a keratin layer, often found in areas subject to less mechanical stress.

Von Ebner Glands

Serous glands associated with the circumvallate papillae that help wash away substances on the tongue to enhance taste.

oral cavity is lined by

stratified squamous epithelium

three variations of oral mucosa 

lining mucosa- floor of mouth cheeks lips 

masticatory mucosa- hard palate and gums

specialized mucosa- tongue surface.

lining mucosa

floor of mouth cheeks lips and soft palate 

unattatched 

nonkartatinized 

soft and pliable 

masticatory mucosa

hard palate, alveolar ridges, and gingiva

keratinized

attached mucosa

in primary contact with food when chewing

specialized mucosa

surface of tongue 

keratinized papilla 

structure of oral mucosa

similar to that of other mucosal tissues

important structures in mucosal tissue

lamina propria

deep reticular layer

submucosa

lining mucosa

thin layer of epithelium and underlying lamina propria 

followed by spinous/ stratum spinosum layer

inner oral surface

non keratinized epithelium

seromucous glands (part of minor salivary glands)

lips have a _____ layer that distinguishes them as tissue transitions

vermillion

ectopic sebaceous glands

seen in buccal mucosa

not associated with hair follicles

known as fordyce granules 

soft palate

highly vascularized lamina dura and more pink than epithelium of the hard palate

buccal mucosa 

similar to lip and soft palate but with fat and mixed seromucous glands 

ventral tongue

similar to other mucosa

submucosa has muscle and connective tissue fibers 

attatched to floor of mouth loosely in comparison to ventral tongue 

minor salivary glands on floor of mouth 

right and left sublingual glands present  

masticatory mucosa

thicker than nonkeratinized

keratin offers resistance to attrition

granular later (granulosum) and keratin layer (corneum) more prominent

keratin is tough and resistant to

seromucus glands

lip

fordyce granule

soft palate

mucus glands with myoepithelium

buccal mucosa

ventral tongue 

keratinized mucosa

keratohyalin granules

parakeratin

nuclei retained keratin 

orthokeratin

nuclei absent from surface keratin

odontogenic keratocyst

lined by parakeratin w/ 25% recurrence rate 

Orthokeratinized odontogenic cyst

lined by orthokeratin w/ 2% recurrence 

parakeratin

orthokeratin

reduced enamel organ epithelium and oral epithelium

fuse as the tooth erupts and result in the production of gingiva as the tooth continues eruption

gingiva divisions

free/marginal- encloses tooth and defines sulcus

attached- portion of epithelium attached to neck of tooth

interdental zone/groove- between two contact points 

indistinct groove separating free and attached gingiva

free gingival groove

free/ marginal zone

gingival zone that encloses the tooth and defines the gingival sulcus

attached gingiva

portion of epithelium attached to the neck of the tooth

interdental zone/groove

gingival area between two teeth beneath the contact point

gingival sulcus

separates tooth from free gingiva

free and attached gingiva

keratinized

alveolar mucosa

nonkeratinized

attached gingiva is

stippled due to attachment sites to underlying alveolar bone

epithelium of gingiva

naturally sheds and exfoliates over time helping to prevent bacteria build up and form immunity to pathogens 

upper gingival sulcus epithelium

not connected to root surface

sulcular epithelium

junctional epithelium

lower gingival sulcus epithelium 

attached to root of tooth 

dentinogingival epithelium

junction between tooth surface and gingival tissues

made of sulcular and junctional epithelium

sulcular/crevicular epithelium 

filled with crevicular fluid 

lines gingival sulcus 

junctional epithelium

begins at the base of sulcus

attached to tooth surface via hemidesmosomes

hard palate 

keratinized stratified squamous epithelium

midline raphe with rugae laterally 

incisive papilla

mucus glands 

traction bands (anchoring palatal mucosa to bone) in the lamina propria of rugae 

hard palate

palate

hard palate

recurrent intraoral herpes

HSV-I

exclusively occurs on keratinized mucosa 

aphthous ulcers

idiopathic occurring on nonkeratinized mucosa

specialized mucosa

anterior of tongue including all epithelial papilla 

filiform papilla 

fungiform papilla

circumvallate papilla

foliate papilla 

von ebner glands 

under circumvallate papilla

aging affects

oral epithelium becomes thinner and fragile 

gradual atrophy of minor salivary glands

fibrosis increases

repair reduces, healing time increased

apical migration of gingiva