oral mucosa Flashcards
what are the functions of the oral mucosa?
-protection
- sensation
- secretion
- absorption
- thermoregulation in animals not humans
what are the types of oral mucosa?
- masticatory (hard palate)
- lining (soft tissues and under tongue)
- gustatory (upper surface of tongue)
describe lining mucosa
- mobile and distensible
- non-keratinised
- loose lamina propria
- wide submucosa
- more rapid turnover than masticatory mucosa
- heals faster as it’s non-keratinised
describe gustatory mucosa
- similar to the masticatory mucosa
- keratinised
- present ONLY on the dorsum of the tongue
- characterised by papillae, some bearing tastebuds
what is the structure of the mucosa structure?
- epithelium
- lamina propria
- submucosa
- bone
describe the layers of the epidermis
- stratum corneum (cornfield layer, keratinised, no nuclei)
- stratum granulosum (granular layer)
- stratum spiniosum (prickle cell layer- cells have peaks)
- stratum germinativum (basal cell layer- cells reproducing/ in mitosis)
what is the top layer of non-keratinised epithelium?
the superficial layer- nuclei in cells
what is the difference between para-keratinised and keratinised epithelium?
- nuclei present in para
- faster cell shedding in para
describe the masticatory mucosa
- hard palate
- firm
- keratinised epithelium
- rete regs
what are rete pegs?
epithelial extensions which project into the underlying connective tissue in skin and mucous membranes
what are tonofilaments?
bundles of packed keratin filaments
what is the structure of the lining mucosa?
- epithelium
- loose lamina propria
- submucosa
- bone/muscle
what is the mucogingival junction?
the junction between the soft, fleshy mucus membrane of the oral cavity and the tough, collagen rich gingiva
what % of epithelial cells do non-keratinocytes make up?
10%
what are non-keratinocytes?
- no keratin
- clear cells
- melanocytes, merkel cells, langerhan’s cells
what is the stratum germinativum?
- also called the stratum basale
- attaches the epidermis to dermis
- deepest layer of epidermis
what are melanocytes?
- pigment producing
- located in the stratum germinativum
what are merkel cells?
- associated with mecanoreceptor neurons
- located in the stratum germinativum
filliform vs fungiform papillae
filliform are more common, rounder, smaller with no taste buds and keratinised
fungiform are mushroom shaped, have tastebuds and sensory nerves, found at tip of tongue and are NON-karatinised
what are vallate papillae?
the largest kind of papillae
describe the structure of the lip
- labial mucosa
- vermillion border
what is geographical tongue?
- oral disease
- irregular smooth dorsal regions
- no filliform papillae
- red/white margins
- pattern changes
- children and adults
- asymptomatic- sometimes uncomfortable
- histologically similar to psoriasis
- no treatment is normally required
what are some diseases of oral mucosa?
- oral infection
- oral ulceration
- vesiculo-bullous lesions
- white patches
- premalignant conditions
- pigmented lesions
- oral cancer