Which nail disease is characterized by thickening of the nails?

Onychogryphosis is the condition known for the thickening of the nails, where the nails become abnormally thick, often resembling the shape of a claw or horn. It typically affects the nails on the toes and is often associated with neglect, trauma, or underlying health issues. The thickened nails can also become distorted in shape, which differentiates this condition from others that might affect nail appearance.

In contrast, onycholysis involves the separation of the nail from the nail bed, which does not directly cause thickening. Onychomycosis refers to a fungal infection that can lead to nail thickening, discoloration, and brittleness, but it does not exclusively define thickening as its primary characteristic. Onychophagy is the term for nail-biting, which leads to nail damage and shortening, rather than thickening. Understanding these distinctions helps clarify why onychogryphosis specifically pertains to thickening of the nails.