Loss of Aβ-nerve endings associated with the Merkel cell-neurite complex in the lesional oral mucosa epithelium of lichen planus and hyperkeratosis

Abstract

Diseases of the mouth lining, or oral mucosa, occur with a loss of nerve endings crucial for sensing touch, research from Germany suggests. The perception of touch in the oral mucosa involves Merkel cells, which join to Aβ-nerve fibres to send impulses to the central nervous system. Yüksel Korkmaz and co-workers at the University of Cologne examined the distribution of Merkel cells and Aβ fibres in healthy tissues and in tissues with the diseases lichen planus and hyperkeratosis. They found that the diseased tissues contained far fewer Aβ-nerve endings, and these were rarely joined to Merkel cells, implying that both diseases impair the sense of touch in the mouth. Based on their findings, the researchers suggest that a healthy mucosa is essential before applying dental prostheses. This will facilitate a harmonic occlusion and protect the oral mucosa against harmful unphysiological occlusal forces, which may occur after impaired sensation in the mouth.

Keywords

Aβ-nerve fibres / hyperkeratosis / lichen planus / mechanosensation / Merkel cell-neurite complex

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