Oral Mucous Membranes Flashcards
What are the main functions of mucous membranes?
-absorption
-excretion
-protection
Where is masticatory mucosa located?
gingiva and hard palate
Where is lining mucosa located?
-alveolar mucosa
-buccal mucosa
-floor of the mouth
-ventral surface of the tongue
-soft palate
Where is specialized mucosa located?
on the dorsal surface of the tongue
Which type of oral mucosa is keratinized?
masticatory
Where are taste buds located?
in specialized mucosa
What is mucoperiosteum?
a periosteum with a mucosal surface (close proximity of mucous membrane) with the periosteum of bone to form an apparent thin layer
What are the two microscopic organizations of oral mucous membranes?
1: epithelium
lamina propria
submucosa
periosteum
2: epithelium
lamina propria
periosteum
What are the layers of cells in the epithelial cell layer?
-stratum corneum (keratin layer)
-stratum granulosum (granular cell layer)
-stratum spinosim (spinous cell layer)
-stratum basale (basal cell layer)
What are some characteristics of stratum corneum?
-no nucleus
-high levels of keratin
What are the epithelial rete pegs?
projections of epithelial tissue that insert into the connective tissue to lock the epithelium into place
What are connective tissue papillae?
projections of connective tissue that interlock with the epithelial rete pegs
What are characteristics of the epithelium of oral membrane mucosa?
-rests on basement membrane
-exhibit one of more specialized intercellular attachments
-avascular
-exhibit a high degree of cellularity and relatively low volume of extracellular matrix
-may exhibit cellular polarity
What does cellular polarity do?
-allows cells to exhibit apical, basal, and lateral borders
-expressed in the distribution of cytoplasmic organelles
What is orthokeratosis?
refers to normal keratin formation with clinically normal presentation
What is parakeratosis?
retention ofpyknotic nuclei in the stratum corneum
What is hyperkeratosis?
abnormal thickening of stratum corneum
-may exhibit aberrant patterns of keratinization
What is dyskeratosis?
abnormal keratinization below the level of the stratum corneum
-keratinization within the stratum granulosum and/or stratum spinosum
What is acanthosis?
refers to hyperplasia of the epithelial layers
(increase in number of cells)
What is acantholysis?
loss of intercellular attachments between epithelial cells
-loss of desmosomes
What is metaplasia?
reversible change in which one adult cell type of replaced by another
-transitions of columnar to squamous epithelium in the respiratory tract due to smoking
What is dysplasia?
disorderly by non-neoplastic growth of tissue including the epithelial layer
-pleomorphism, hyper chromatism, and loss of normal spatial orientation
-could be a sign of precancerous conditions
What type of keratinized cell is present?
gingival parakeratosis (nucleus retained in the stratum corneum)
What type of keratinized cell is present?
gingival hyperkeratinization (very thick stratum corneum)