Nail biting is a disease that is medically known as Onychophagia. It is a common oral compulsive habit in kids and elders. It is classified under the impulsive control disorder. Nail biting is a serious problem that may result in various infections. Improper hygiene of hands may be a cause of various worms in stomach in which pinworms is common. Nail biting can result in broken and exposed cuticles that can be attacked by a bacteria, virus or fungus. It is sometimes related to dental problems such as malocclusion of the forward teeth and gingival injury. Nail biting is a common habit among both children and adults. Numbers of adult that are affected by this disease are way more than the number of children. About 30% children of 7-10 years of age and 45% adults are affected by this disease.
Obsessive-compulsive disorder (OCD) is a psychological condition and nail biting is a prominent symbol for this disorder. Nail biting is generally seen in children, which may be due to psychiatric disorders especially like attention deficit hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), separation anxiety disorder, or bed-wetting. Nail biting on regular basis is considered as self-mutilation as it causes severe damage to nails and the respective fingers.