The ingrown nail

Anatomy of the nail

Finger and toenails act as tools and provide a protective function as contra plates for nerve sensors. A nail is made up of 100 to 150 unevenly superimposed layers of horny cells, usually between 0.5 and 0.7 mm thick. They are firmly joined to the nail bed. Different nails grow at different speeds. Finger nails only take a week to grow about 1mm, whereas toenails take a month. The cornification process deep in the nail bed is responsible for the growth of the nail. The cornificated keratin is slowly pushed forward.

What is an ingrown toenail?

An ingrown nail is medically termed Onychocryptosis. In this situation, the side or distal edge of the nail presses into the skin and leads to discomfort, pain and in most cases inflammation (Paronychia).  
Ingrown nails are usually a result of the nail bed being too low, causing the nail to be unable to grow over the proximal nail fold and thus it grows into the skin resulting in irritation and inflammation. Once the nail pierces the skin, the body’s bacterial flora infects the wound and hyper-granulation tissue may form. 

Another case of ingrown toenails describes an involuted, curved nail that presses on the underlying tissue in the sulci of the nails. This pressure results in painful corns and callous forming under the nail. In come cases the nail can almost curl back on itself, to the point that is actually squeezes the nail bed. These are called pincer nails.

The reason for an ingrown nail

The cause of ingrown nails is usually a result of incorrectly fitting footwear, incorrect nail trimming, injury to the nail or genetic predispositions.