Nail Growth
Like the hair, the nail is made of keratin (hardened) protein. Although nail protein is much harder
than the protein of hair, its growth is similar to the growth of hair. You already know that hair grows
from a pocket-like structure called the follicle, originating from a row of reproducing cells called the
germinal matrix. As these cells multiply, they are pushed upward and keratinize into the layers of
the hair (cuticle, cortex, medulla). By the time the hair reaches the skin's surface, it is hardened and
takes the shape of a hair strand. The same is true for nails.
Nail growth originates from active tissue known as the matrix, located in the mantle. The matrix
contains lymph, blood vessels and nerves that create cells, which are pushed outward from the nail
root. These cells keratinize (harden) as they continue toward the nail body (plate) and become fully
hardened by the time they reach the eponychium. These hardened cells form the visible nail body
(plate) that curves on the sides and travels in tracks found on the side of the nail called nail grooves.
The nail plate can be thin, normal or thick, depending on the rate of production of cells in the matrix.
Under normal circumstances, growth of a new nail plate takes about four to six months.
The
nail bed on which the nail body (plate) rests contains many nerves, as well as blood vessels for con-
tinuous nourishment.
Nails grow at an average rate of 1/8 inch (.35 cm) per month in adults. Nails grow more
rapidly in younger people because general cell reproduction is occurring at a faster rate.
Thus, as one ages, the growth of nails slows down.
Nail growth is faster in summer than in winter, and can be affected by nutrition, health or
disease.
The thumb nail grows slowest, while the nail on the middle finger grows fastest.
Toenails
are harder and thicker than fingernails but grow more slowly.
Injuries to the nail can result in shape distortions or nail discoloration.
Most nail injuries are
minor and resulting distortions and/or discoloration are temporary. Permanent distortions can occur
when:
· A nail is lost due to trauma and, without the protection of the nail plate, the nail bed
or matrix is injured.
· A nail is lost through disease or infection. The regrown nail, in these circumstances,
is often distorted in shape.
Nail Diseases, Disorders and Conditions
Any disease, disorder or condition of the nail is called an onychosis
(on-i-KO-sis).
· If a disease is present, no nail service can be performed; the client must be referred
to a physician.
· If a disorder is present, nail services may be done with care; the client may want to
consult a physician for help and information.
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SALON FUNDAMENTALS
