Oral Mucosa Flashcards
What are the functions of oral mucosa?
- Protection (mechanical, against infection, immunity)
- Sensation
- Secretion
- Absorption
- (Thermoregulation)
What are the 3 types of oral mucosa?
Lining, masticatory, gustatory
Where is masticatory mucosa found?
The hard palate and gingiva
Where is lining mucosa found?
Ventral surface of tongue, labial surface, buccal surface, soft palate
Where is gustatory mucosa found?
Tongue dorsum
Describe the features of masticatory mucosa
- Subjected to friction, compression
- (Para)keratinised
- Thick lamina propria (mucoperiosteum)
Describe the features of lining mucosa
- Mobile and distensible
- Non-keratinised
- Loose lamina propria and wide submucosa
- More rapid turnover than masticatory mucosa
Which type of mucosa is has more rapid turnover: masticatory or lining?
Lining mucosa
Describe the features of gustatory mucosa
- Similar to masticatory mucosa
- Keratinised
- Present only on dorsum of tongue
- Characterised by papillae, some bearing taste buds
What are the layers present in epithelium?
- Basal layer/stratum germinativum (mitotic cells here)
- Stratum spinosum (prickle cell layer - contains desmosomes)
- Statum granulosum (granular layer
- Stratum corneum (cornified layer - contains keratin)
Describe the sturcture of mucosa
Epithelium
Lamina propria
Submucosa
Bone
Describe the following types of epithelium:
- Non-keratinsed: no stratum corneum
- Parakeratinised: cornified surface. Still find some nuclei in this area
- Keratinised: Intermediate layer and superficial layer instead of granular layer and keratinised layer
Why can lining mucosa heal faster than masticatory and gustatory mucosa?
Because lining mucosa is non-keratinised. Non-keratinised tissue can heal quicker as keratinisation slows the process
Which mucosal layer is absent in masticatory mucosa?
Submucosa - this makes the tissue very tight
Describe the submucosa layer in lining mucosa
Flexible/loose lamina propria
Where is the mucogingival junction?
Between alveolar mucosa and gingiva
What percentage of epithelial cells do non-keratinocytes account for?
10%
What are melanocytes and where are they located?
Pigment producing cells located in the stratum germinativum i.e. the basal layer
Where would you find Merkel cells?
In the stratum germinativum - basal layer
What are 3 examples of non-keratinocytes?
Melcanocytes, Merkel cells and Langerhans cells
What are Langerhans cells and where are they located?
Dendritic cells (DCs), found above the stratum germinativum; function as antigen presenting cells
What are Merkel cells?
Mechanoreceptors
Why is the tongue rough?
Due to projections called papillae
What are taste buds?
Chemoreceptors: recognise specific chemicals
