Ingrown nail is a deformed nail with the sides curling to grows so that it cuts into one or both sides of the nail bed. If there is no pain or inflammation, there is no need of treatment.

To control the pain or appearance, the management includes topical agent, stuffing cotton, or partial removal of the nail under local anesthesia (block anesthesia). Cutting the nail too short is one of the aggravating factors and the patients are encouraged to keep the nail long enough while adopting the above mentioned methods.  If none of these is effective to control the pain, the correction wire method (not covered by Japanese health insurance) or the phenol cauterization is the next step to take. The cure rate after the phenol cauterization is said to be 90-95%, but those with diabetes have no indication for this method.