Disappearing Nail Bed: Review of Etiology, Grading System, and Treatment Options.

Disappearing nail bed (DNB) is a condition characterized by irreversible epithelialization of the nail bed following long-standing onycholysis. This phenomenon can occur in fingernails and toenails. Factors implicated in the development of DNB include trauma, manicuring, and onychotillomania and dermatologic conditions like psoriasis and dermatitis. Specifically for the toenail, contributing factors also include increasing age, history of trauma, surgery, onychomycosis, and onychogryphosis. A grading system that stages the progression of onycholysis to DNB has been proposed to aid clinicians in the diagnosis and treatment of these conditions. Several methods have been designated for the treatment of DNB.