Signs of infection include redness and swelling of the area around the nail, drainage of pus, and watery discharge tinged with blood.

The main contributor to onychocryptosis is footwear, particularly ill-fitting shoes with inadequate toe box room and tight stockings that apply pressure to the top or side of the foot.

[5][6] Other factors may include the damp atmosphere of enclosed shoes, which soften the nail plate and cause swelling on the epidermal keratin (eventually increasing the convex arch permanently), genetics, trauma, and disease.

[9] Ingrown toenails are caused by weight-bearing (activities such as walking and running) in patients that have too much soft skin tissue on the sides of their nail.

However, failure to treat the cutaneous condition can result in a return of the ingrowth and a deformity or mutilation of the nail.

Proper cutting leaves the leading edge of the nail free of the flesh, precluding it from growing into the toe.

Some nails require cutting of the corners far back to remove edges that dig into the flesh; this is often done as a partial wedge resection by a podiatrist.

Injury to the nail can cause it to grow abnormally, making it wider or thicker than normal, or even bulged or crooked.

[10] Mild to moderate cases are often treated conservatively with warm water and epsom salt soaks, antibacterial ointment and the use of dental floss.

[11] Some over-the-counter ingrown toenail pain relief kits include a sodium sulfide gel with cushions and elastic bandages.

In studies of diabetics, who need to avoid surgery when possible, nail bracing was found to be effective at providing immediate, as well as long-term, relief.

[10] If the ingrown toenail recurs despite this treatment, destruction of the sides of the nail with chemicals or excision is done; this is known as a matrixectomy.