Melanocytes in Oral Epithelium: Origin, Features, and Function

Melanocytes in Oral Epithelium: Origin, Features, and Function

Question 1. Melanocytes.
Answer:

Origin:

• Embryologic neural crest cells.

Features:

• Dendritic cell.
• Do not possess desmosomes and tonofilaments.
• Stores melanin pigment in melanosomes.
• They are present in the basal layer of epithelium.

Function:

• Synthesize melanin pigment.
• Transfer to surrounding keratinocytes.

Question 2. Dentinogingival junction.
Answer:

• It is the junction between the gingiva and the tooth.
• It represents a potential weakness in the epithelial lining of the oral cavity.
• The firmness and mechanical strength of the dentinogingival junction are due to the connective tissue attachment.
• It is less resistant to mechanical forces and bacterial attacks.
• Firmness of it is maintained by the gingival portion of the periodontal ligament.
• The epithelium of the gingiva which gets attached to the tooth is called attachment epithelium.
• The adherence of epithelium to the tooth is the function of attachment epithelium.

Question 3. Changes In oral mucosa.
Answer:

• The oral mucosa becomes smooth and dry.
• Decreased salivary secretion.

Histological changes:

• Epithelium appears thinner
• Smoothing of the epithelium-connective tissue interface
• Flattening of epithelial ridges.
• Reduction in filiform papillae.
• Reduction in Langerhans cells.
• Development of varicosities.
• In lamina propria.
• Decreased cell hilarity
• An increased amount of collagen.
• Atrophy of minor salivary glands
• The decline in cell-mediated immunity

Changes in postmenopausal women:

• Dryness of the mouth
• Burning sensations
• Abnormal taste.

Nerve changes:

• Progressive loss of sensitivity to thermal, chemical, and mechanical stimuli.
• A decline in taste perception.