The shortening of the nail bed due to nail chewing is a human-induced shortening of the nail bed. Therefore, if you stop chewing your nails, the shortening of the nail bed can usually be restored. Long-term nail gnawing leads to shortening of the nail bed, which is medically known as nail biting fetish. It is most common in children and adolescents, and the causes of its onset are mental stress, imitation of family members, and the transfer of thumb-sucking habits. There is no pathologic factor in the onset of nail biting fetish, which is a habitual human factor of nail biting that shortens the nail plate and then the nail bed. The exposed part of the nail is the nail plate, the skin under the nail plate is the nail bed, the part that extends into the skin is the nail root, and under the nail root is the nail matrix, which is the growth area of the nail. Since the nail biter chews on the end of the nail, the nail matrix is not damaged, so the shortening of the nail bed usually recovers when the biter stops chewing on the nail. This disease does not require drug treatment, should be carefully observed to make the patient’s disturbing factors, through psychological counseling and other ways to eliminate the disturbing factors, or let the patient to participate in sports, to divert their attention, so that they no longer habitually gnawing nails.