Exam 3 - Oral Mucosa Colombo Flashcards
What lines the oral cavity and where does it transition to respiratory/GI mucosa?
Oral mucosa; tonsillar pillars
The oral mucosa is composed of:
- stratified squamous epithelium
- underlying lamina propria
- may also have submucosa
Submucosa
Deeper connective tissue layer containing glands, etc.
Oral mucosa is characterized on the basis of:
Keratinization
Areas that are keratinized are generally:
Areas that need more protection
Areas that require more range of movement are:
Non-keratinized
Orthokeratinized
Squames do not contain any visible nuclei
Parakeratinized
Squames still have some proportion of visible shrunken (pyknotic) nuclei
Keratinized epithelium can either be:
- orthokeratinized
- parakeratinized
In the oral epithelium, where does cell renewal take place?
Basal layer (stratum basale)
In the oral epithelium, what is above the basal layer?
Prickle cell layer (stratum spinosum)
What happens to cells in the prickle cell layer?
- cells get noticeably larger, start filling with organelles
- shrink when fixed except where they are connected to one another
Keratinized epithelium has a ___ layer packed with ____ which assemble keratin filaments
Granular layer (stratum granulosum); keratohyaline granules
Keratinized epithelium is topped by a layer of keratin packed squames called:
Cornified layer/stratum corneum
Non-keratinized epithelium contains
intermediate layer and top superficial layer
Upper layer of the lamina propria contains:
blood vessels
In keratinized oral epithelium, cell maturation takes place in layers, which are:
- basal layer
- prickle cell layer
- Granular intermediate layer
- keratinized surface layer (stratum corneum)
In non keratinized oral epithelium, cell maturation takes place in layers, which are:
- basal layer
- prickle cell layer
- intermediate layer
- superficial layer
What are rete pegs?
- Interlocking ridges of connective tissue and overlaying epithelium in the oral mucosa
- projections of epithelium into underlying lamina propria
Connective tissue counterparts of rete pegs
Connective tissue papillae
Rete pegs are important for:
providing mechanical resiliency of tissue (like shear on the basement membrane)
Rete pegs can give the gingiva a ___ appearance
Stippled
Rete pegs are more pronounced in:
Keratinized epithelium covering gingiva or palate
Rete pegs are broader and less defined in:
Non keratinized lining mucosa
Damage to tissues via inflammatory disease can result in:
Loss of rete pegs
Besides epithelial cells, what other cell types are found in the oral epithelium?
- Melanocytes
- Langerhans cells
- Merkel cells
- lymphocytes
Melanocytes - function and origin
- provide pigmentation (not based on number, more so melanin production)
- origin is neural crest
Langerhans cells in the oral epithelium
Dendritic cells (APC); migratory
Merkel cells - location and function
- located in basal cell layer of oral epithelium
- associated with nerve fibers/touch sensation (deep static touch)
Lymphocytes in the junctional epithelium
occasionally present; infiltrate inflammatory situation
_____ functions as mechanical support to the epithelium and carries blood vessels/nerves
Lamina propria
Lamina propria layers
- papillary layer
- reticular layer
Papillary layer of lamina propria
- directly under epithelial layer
- loose connective tissue
- more cells
Reticular layer of lamina propria
dense connective tissue fibrous layer under papillary layer
The oral mucosa of the cheek has a thinner or thicker lamina propria than the outer surface of the lip
Thinner
_____ is a source of unique mesenchymal progenitor cells
Oral lamina propria
____ interdigitates with epithelial rete pegs
Connective tissue papillae (lamina propria)
Oral fissure
Another term for opening of the mouth
What is the space that the mouth opens on to?
Oral cavity (until it transitions to the oropharynx)
The oral cavity is the gateway to the:
- GI tract
- respiratory tract
Functions of the oral cavity
- nutrition
- communication
- social interaction
- self defense
Subdivisions of the oral cavity
- oral vestibule
- oral cavity proper
3 classifications of the oral mucosa
- lining mucosa
- masticatory mucosa
- specialized mucosa
Lining mucosa is keratinized or nonkeratinized?
Nonkeratinized
Lining mucosa covers what structures?
- lips
- cheeks
- floor of the mouth
- soft palate
- alveolar mucosa
- ventral side of tongue
The lining mucosa is fairly ____ except for the labial and buccal
Thin
Thinnest area of the mouth/clinical significance
Floor of the mouth - often used for medication delivery
Masticatory mucosa is keratinized or nonkeratinized?
Keratinized
Masticatory mucosa is found on:
- gingiva
- hard palate
Is masticatory mucosa thin or thick?
Thick
Specialized mucosa - keratinized or nonkeratinized?
Generally keratinized
Where is specialized mucosa found?
- dorsal surface of the tongue (with all the papillae)
Is specialized mucosa thin or thick?
Thick
What are the junctions of the oral mucosa?
- mucocutaneous
- mucogingival
- dentogingival
Mucocutaneous junction
transition area between skin and oral mucous membrane
Vermillion zone
- “red/pink/purple” part of the lip
Vermillion zone contains ____ epithelium
thin, keratinized
What causes the distinct color of the vermillion zone?
long connective papillae with abundant capillary loops
What is the vermillion border?
Border separating vermillion zone and outer skin
Intermediate zone
transition between vermillion zone and labial mucosa
The intermediate zone is made of ____ epithelium
Parakeratinized stratified squamous epithelium
The mucogingival junction shows a marked transition between:
Epithelium of the alveolar mucosa and epithelium of attached gingiva
Attached gingiva is located between:
Mucogingival junction and free gingival groove
The alveolar lining mucosa contains:
Abundant elastic fibers and high degree of mobility
Attached gingiva epithelium is:
Keratinized stratified squamous
Attached gingiva epithelium typically shows ____ in a healthy mouth due to ____
Stippling; increased numbers of collagen bundles and more prominent rete pegs
What marks the start of the free gingiva
Free gingival groove
Free gingiva is also known as
Marginal gingiva
Free gingiva is bounded by:
- free gingival groove
- free gingival margin
- gingival sulcus
- vestibule and oral cavity
Free gingiva epithelium is generally:
Keratinized (but can be para or non)
Sulcular epithelium lines the ____ and is _____
gingival sulcus; nonkeratinized
Sulcular epithelium is thinner and lacks
Pronounced rete pegs
The sulcular epithelium is continuous with:
Junctional epithelium
Junctional epithelium is keratinized or not?
Nonkeratinized
Interdental papillae
Between the teeth just under the interdental contact area
Interdental papillae composed of
Keratinized stratified squamous epithelium
Col
concave depression between peaks of interdental papillae
Col is generally lined with
Nonkeratinized stratified squamous epithelium
Two main components to the dentogingival junction/junctional epithelial area
- junctional epithelium
- underlying connective tissue (supports and instructs the junctional epithelium)
Epithelial structure of dentogingival junction
2 basal laminae (one at tooth surface, one at junctional epithelium)
Dentogingival junction is highly influenced by
Inflammatory signals
What forms the floor of the gingival sulcus
Junctional epithelium
Junctional epithelium is derived from
Coronal reduced enamel epithelium during tooth eruption
Establishment of junctional epithelium: as the tooth erupts, the REE ____
fuses with oral epithelium; flattened outer layer of epithelium attaches to tooth surface
_____ underlying junctional epithelium sends signals to the overlying epithelium
Connective tissue
(signals may be responsible for specialized characteristics)
____ are heavily influential in the gingival and sulcular/junctional epithelium
Inflammatory cells
Gingival connective tissue does not have a heavy traffic or inflammatory cells- thus, the epithelium is:
In contrast, sulcular and junctional epithelium is supported by connective tissue with a fair number of inflammatory cells, thus held in ____ state
Keratinized; non keratinized
Antibiotics and intense oral hygiene in experimental animals results in
Sulcular/junctional epithelial keratinization
Apical movement of the periodontal pocket may be caused by
- Inflammatory loss of underlying connective tissues
- proliferation/downward migration of the junctional epithelium
Oral mucoperiosteum structure
- medial hard palate
- attached gingiva
- no submucosa
- robust lamina propria attaches directly to bone
Soft palate has lining mucosa so it is not
Keratinized
Can find glandular tissue on
Soft palate
What separates oral and nasal cavities
Soft palate (thus one side has respiratory epithelium)
Hard palate contains masticatory epithelium to withstand
Abrasion
Hard palate epithelium
Masticatory - keratinized stratified squamous ortho/para
Hard palate - lamina propria often binds:
Directly to the underlying bone
True or false: some glandular tissue present on hard palate
True (more so on soft palate)
Anterior region of hard palate features
Rugae that do not cross palatine median raphe
Lamina propria attached directly to underlying bone (no submucosa) in ___
Mucoperiosteum
Laterally, both anterior and posterior palate may have ____ but median typically does not
Submucosa
Junctional epithelium abuts the ____ and forms _______ to the tooth surface
tooth; hemidesmosomal attachments
