Onychophagia - Causes, Diagnosis, and Treatment

Introduction

Onychophagia is the clinical term for fingernail biting. It is a common stress-related or nervous habit typically observed in children and adults. This refers to biting the hard surface of the nail and occasionally biting the softer skin surrounding the nail bed and the cuticle. Onychophagia is also referred to as onychotillomania. It includes the practice of picking or manipulating nails. Some investigators accept that nail-biting results from a delay or dysfunction in the oral stage of psychological growth.

What Is Onychophagia?

Onychophagia or nail biting (nail biting) has been a common topic in psychiatry and dermatology. The problem of nail biting has been unable to resolve in medicine, psychology, and dentistry. While individuals practicing nail biting usually like to stop it, their steps to end it have failed. The parents of a sizable number of children, who are guided to clinics to manage nail biting, have tried to help their children by coating nail plates with an undesirable taste. Sometimes they have covered the nails with rubber or cloth finger protectors. These measures only occasionally lead to a permanent fading of this behavior. Many children with nail biting behavior may be disciplined by their parents or family members. Punishment and threat may not lead to a reduction in nail biting frequency. Instead, it may lead to an increase in its frequency. Individuals with nail biting behavior may say they are helpless or unable to stop this avoided behavior. It is believed that nail biting may guide clinicians to better pharmacological management of children with attention deficit hyperactivity disorder (ADHD).

What Causes Onychophagia?

"Keeping one or more fingers in the mouth and biting on the nail with teeth" is the operational definition of nail biting. Nail-biting is not a pathological condition. However, the border between nail biting's healthy and unhealthy behavior has yet to be discovered. Nail biting in healthy children does not last very long, and it is temporary. However, the frequency, intensity, and duration of pathological nail biting are more than those in normal individuals. The psychiatric disorder classification also echoes the importance of pathological and non-pathological nail biting. Some behavioral problems like trichotillomania are classified as impulse control conditions in DSM-IV (diagnostic and statistical manual of mental disorders, fourth edition), and nail biting is not classified in DSM-IV. Nail biting can also be categorized as self-injurious behavior, including pathological skin-picking or a stereotypic movement disorder. It is also believed that nail biting is a part of the obsessive-compulsive disorder spectrum.

Some of the causes of onychophagia are mentioned below.

• Behavioral problems.

• Anxiety.

• Oral aggression.

• Malocclusion development.

• Nail biting usually occurs as a consequence of boredom.

• Working on complex problems.

Other conditions associated with onychophagia are mentioned below.

• Attention deficit hyperactivity disorder.

• Oppositional defiant disorder.

• Separation anxiety disorder.

• Other comorbid disorders include enuresis.

• Tic disorder.

• Obsessive-compulsive disorder.

• Major depressive disorder.

• Mental retardation.

• Pervasive developmental disorder.

• Tourette syndrome.

• Anxiety disorders.

• Common co-occurring stereotypic behaviors were lip biting and head banging.

Some of the physical problems associated with nail biting are:

• Swallowing the bitten nails causes stomach infections.

• Onychomycosis (fungal infections of the nail plate) and paronychia (surrounding skin).

• Resorption in teeth root.

• Alveolar destruction.

• Intestinal parasitic infections.

• Pain and dysfunction in the temporomandibular joint.

How Is Onychophagia Diagnosed?

Observation for nail biting in the analysis room, thorough non-judgmental questioning of the patient's nail habits, and physical examination are essential to determine onychophagia in the early stages.

Inspection of all twenty nail units is suggested for diagnosing onychophagia. In addition, a full-body skin examination, including the scalp and secondary hair, is conducted to look for other symptoms of other body-focused repetitive behavior (BFRBs) like skin picking, hair pulling, and nail picking, as they may also be present. Chronic nail biters are more likely to appear with orodental abnormalities; therefore, an inspection of the oral mucosa must be noticed.

Patients with onychophagia generally present with abnormally short, uneven nails and absent, ragged cuticles. Nail folds in different stages of healing are also present. Visible changes in the nail and periungual regions are seen. It includes linear and pinpoints hemorrhages, longitudinal melanonychia, transverse grooves, brittleness, macro lunula, and pterygium, a scar in the nail matrix. Dermatoscopic evaluation of onychophagia reveals loss of nail plate with ragged distal nail borders. Onychophagia usually occurs in the fingernails, as toenails are rarely bitten. Because toenails are physically harder to bite, toenail biting indicates possible psychiatric comorbidities.

What Are the Dental Problems Associated With Nail-Biting?

Untreated, severe onychophagia can lead to dysmorphic dental problems. Some of the dental problems are mentioned below.

• Malocclusion, front teeth are misaligned.

• Crowding.

• Attrition.

• Rotation of the teeth recorded on X-rays.

• Attrition of the incisional edge of the lower front teeth (mandibular incisors).

• Protrusion of the upper front teeth (maxillary incisors).

Dysmorphic dental problems can impact a person's physical appearance, but this can be bypassed if the nail-biting habit is managed earlier.

How Is Onychophagia Treated?

The onychophagia treatment is based on the severity of the nail-biting habit.

• No treatment is required for mild onychophagia, as a child can often withdraw and outgrow the habit.

• Dermatologists suggest keeping the short nails trimmed, manicured, or covered to minimize the temptation to nail biting.

• The application of bitter-tasting compounds to the nails to discourage nail biting is controversial and not very effective.

• Behavior modification treatment.

• Any underlying mental health problem or psychiatric disorder should be treated.

Conclusion

Onychophagia or nail biting, a cosmetic concern, can be described as a temporary and non-destructive behavior. But it can also become a severe, long-term problem with some complications. Onychophagia, or onychophagy, is viewed as a pathological oral habit and grooming disorder. Therefore, early diagnosis is made, and prompt treatment is provided to avoid and withdraw the symptoms and complications of onychophagia.