Onychatrophia

Also known as atrophy describes the wasting away of the nail. The nail loses its shine, shrinks, and falls. This can be caused by injury to the nail matrix or by internal disease. Handle this condition with care.

Onychauxis
Show the opposite symptoms of onychatrophia. Nails with this disorder are abnormally thick. The condition is usually caused by internal imbalance, local infection, or heredity. File the nail until smooth and buff

Onychocryptosis
Ingrown nails is a familiar condition of the fingers and toes in which the nail grows into the sides of the tissue around the nail. If the nail is not too deeply imbedded in the flesh, you can trim the corner of the nail in a curved shape to relieve the pressure on nail groove. If it is deep they should see a doctor.

Onychophagy
Is the medical term for nails that have been bitten enough to become deformed.  This condition can be greatly improved by regular manicures or artificial nails. It is not realistic to tell a nail biter to come back for artificial nails after they have grown a free edge.  Artificial nails can help this person break the biting habit.  There are also nail biting topically applied remedies available.

Onychorrhexis
Refers to split or brittle nails that also have a series of lengthwise ridges. It can be caused by chemicals, injury to the fingers, excessive use of cuticle solvents, nail polish removers and careless rough filing. This condition may be corrected by softening the nails with a reconditioning treatment and discontinuing the abuse.