Nails are made up of keratin plates and are designed to protect the tips of fingers although they function as useful tools as well. The main area of a nail is called the nail plate which contains no blood vessels or nerves. The nail root lies under the cuticle at the base of the nail and the hard translucent nail plate is made up of a compact form of protein known as keratin.

Nail Development & Growth

The nail develops in the embryo as the epidermis folds to form a nail fold. At 3 months of development the fold thickens on each finger. Nail formation is completed at the fifth month of development when they reach the tips of the fingers. The growth of nails is continuous throughout life although the rate of growth varies from person to person.

With age, blood circulation at the root becomes less efficient which leads to a gradual slowing of the nail growth. The effect of ageing may be increased by nutritional deficiencies related to a poor diet as well as chronic disease. Nails become thicker and opaque resulting in a yellow to gray color and the moisture of the nails are reduced, resulting in fragile nails causing the nails to either flake in layers or develop fissures.

Internal physiological conditions such as poor circulation, anemia and psoriasis may cause disorders of the nail. Self-inflicted conditions such as misuse, accident or nail biting are also causes of nail defects. Fungal infections of the nail (onychomycosis) is common on the toenails and especially on the fingernails due to prolonged use of acrylic nails.

Brittle nails (Fragilitas unguium)

Frequent usage of detergents may lead to dehydration of the nails due to the constant removal of protective oils. Brittle nails have a decreased amount of water in the nail plate and a deficiency in blood supply of the matrix. Poor blood circulation or iron deficiency can impair nail growth leading to the thinning of the nail plate. Water is easily lost from a thin nail resulting in brittle nails.

Gelatin is recommended for brittle nails as it is a protein which helps for tissue repair. The use of cuticle cream massaged into the nail area and avoid overuse of detergents will be beneficial in preventing the nails from drying out.

Furrows and Ridges

A transverse furrow on the nail may follow after a serious illness and could also be a sign of respiratory disorders, seen in long time smokers. The lines are an interference with the nail growth and appear several weeks after the illness and may take 3 to 4 months to grow out. Furrows and ridges in smokers persist for years, even after quitting smoking.

Hang nails

A hang nail is a piece of nail growing in the nail groove separately from the main nail. This may result from injury to the nail root, nail biting or the dryness of the nail. If allowed to grow the hang nail may be pulled away from the skin resulting in an infection of the area. If inflammation occurs it should be treated with an antiseptic cream.

Ingrown nails

Onychocryptosis, commonly known as an ingrown nail, occurs when the nail plate is cut too short at the corners of the nails. This results in the nail growing into the sides of the wall causing inflammation. Toe nails are more prone than finger nails as the tips of the nail are constantly under pressure from the shoe.

Nail biting

Nail biting or onychophagy results in the distortion of the nail, most commonly seen when the nail is bitten too deep, resulting in a ragged appearance. This habit usually starts in childhood and is very difficult to break. While the habit should be stopped, a cuticle massage may improve circulation and encourage nail growth. The bitten nails should be trimmed to give a neat appearance and prevent ingrown nails.

Discoloration of the Nail

Nails may become discolored by damage of the nail bed, fungal infection, or substances that stain the nail plate. A fungal infection of the nail (ringworm) may cause the nail to become yellow, brown, or black and powdery. An antifungal application is required or the fungus will persist, spread and cause severe deformity of the nail. Nicotine and hair dyes stain the nail plate yellow and some dark red nail enamel used without a based coat may also contribute to nail staining that is not easily removed with acetone.