Nail biting (onychophagia) is a common oral compulsive habit in children and young adults. Nail biting usually starts at the age of around five in children. It starts as the child’s dental development begins. It affects around 30% of children between 7 to 10 years and 45% of teenagers

Causes
The main cause is insecurity in the infant, early weaning or long hours of absence of the mother from the child’s sight, as is with any habit disorder. If not, a subconscious sense of insecurity begins to creep in if they feel that their mother is not close by, which affects their social and emotional interactions.
Nail biting also signifies nervousness, and, later on in life, before you know it, it’s turned into an uncontrollable habit. There may be a genetic component as nail-biting is more common when parents were nail-biters as children and twins are likely to start biting their nails at the same time. Children are also great imitators. If an adult in the household or family is a nail-biter, the child may think, “That looks like fun!” Thus, environmental as well as genetic factors play a role.

Ill-Effects
*Bitten fingertips can become very sensitive to pain; usually at the place the skin meets the edge of the nail.
*Hangnails are broken skin on the cuticle. When they are improperly removed, they are susceptible to microbial and viral infections producing whitlows.
*Finally it may also result in the transportation of bacteria that are buried under the surface of the nail, or pinworms from anus region to mouth. Nail biting is also related to dental problems, such as gingival injury.
*Regarding social effects the aesthetic aspect of the nail may affect employability, self-esteem, and interaction with other people. They begin to feel as if friends or even family will not accept them. Such children are not able to face the demands of their environment and these emotional scars remain with them all their lives.

Prevention Methods
As we can see, nail biting is a habit disorder, which may be overlooked in children, but you have a problem, when that child continues to rip at his nails even as he becomes an adult. This psychological problem should be tackled at a very early stage, for if left uncorrected, it can last for a lifetime. This child is normally quite nervous and jumpy as he is embarrassed by his own behavioral disorder. Unfortunately, since he starts biting his nails unconsciously, it is difficult for him to stop. In extreme cases, fingers can also start bleeding.
*Keep his hands occupied
*Observe him
*Something bitter
*Speak to your child
*Don’t nag
*Cut the nails

And finally…
A warm and loving environment is instrumental in stopping this habit since nail-biting is primarily psychological in nature.