Clinical and dermoscopic characteristics of onychophagia and onychotillomania: a retrospective study of 63 cases.

Onychophagia and onychotillomania are common forms of nail-biting and nail-picking disorders, but there is insufficient literature documenting their comparison and coexistence. In fact, overlapping features can be involved in different nail self-injuries, and significant variations also exist. We conducted a retrospective study aimed at identifying differences between onychophagia and onychotillomania, and providing more detailed findings of both conditions.