The etiology of fingernail depressions is often difficult to pinpoint.
The first step is to improve lifestyle habits, such as reducing exposure to detergents, oils or irritants, avoiding excessive nail trimming or damage to the nail crease, improving nutrition and eating a balanced diet, and watching for recovery on its own.
If the nail does not recover, it is advisable to see a doctor to determine if there are any other systemic factors and to treat them accordingly.
Usually when the cause is correctly removed and treated, the nail is gradually replaced by a newly grown normal nail as it is metabolised, thus allowing a gradual return to normal.