What are Oral Parafunctional Habits? – Let’s Find Out

Many people in the world develop an uncontrollable habit of biting the nails or clenching the teeth tightly. And often, this habit becomes an unconscious act that the patient follows throughout life. Now, you may think that it is not such a big deal to have a simple habit of nail-biting. However, these oral parafunctional habits can have severe effects on your oral health over time.

Oral parafunctional habits are typically described as abnormal functioning of the oral tissues and muscles.

Some of the everyday parafunctional habits include teeth grinding or bruxism, nail-biting, tongue thrusting, thumb sucking, and mouth breathing. It is essential to bring your attention to any of the above-mentioned parafunctional habits. Moreover, it is necessary to manage these oral habits and prevent damage to oral tissues.


Treatment of parafunctional habits usually depends on the cause. A dentist can help to identify the pattern and its definitive cause during a routine dental check-up. Today’s article will highlight the different types of oral parafunctional habits and management.

What do you mean by oral parafunctional habits?

Oral parafunctional habits are categorized as the habitual exercise of the mouth and jaws, which are different from the everyday functional movements. Some of the standard parafunctional practices involving the mouth, jaw, and tongue include bruxism, tongue thrusting, finger nail-biting, and mouth breathing.

Parafunctional habits are typically prevalent among children and young adults. Most people adapt parafunctional habits as a protective reflex. During this time, an extreme amount of force is put on the teeth. This is the reason why parafunctional practices are also considered as the most destructive oral habit.

What are the effects of parafunctional habits on oral health?

Oral parafunctional habits are often involuntary actions. Usually, such activities can have some of the most devastating effects on the teeth and other oral tissues. Some of the signs and symptoms of oral parafunctional habits are listed below –

  • Tooth wear like attrition and abrasion
  • Developments of temporomandibular joint disorders (1)
  • Malocclusions like excessive overjet, open bite, and crowding of the teeth
  • Speech impairment
  • Obstructive sleep apnea
  • Scalloping on the tongue surface
  • Dysphagia
  • Forward head posture
  • Jaw muscle pain and discomfort

It is essential to address the signs and symptoms mentioned above immediately. Moreover, consult the dentist to treat the habit and prevent further damage to the teeth and oral tissues.

What are the different types of parafunctional habits?

Parafunctional habits are involuntary practices, which means that these activities are usually performed under the unconscious will of a person. Some of these daily habits are more evident than others. Following is a list of all the everyday parafunctional practices of the mouth –


Bruxism infographic

Bruxism is a clinical term which is given to teeth grinding or clenching of the teeth. Usually, teeth come in contact with one another while eating or chewing food. However, bruxism is a parafunctional habit that a person usually develops as a protective reflex against anger, anxiety, or stress. (2)

Mostly, a person with bruxism performs this activity during sleep. This is one of the reasons why people with bruxism may be unaware of their habit. Occasional teeth grinding doesn’t adversely affect the health of the teeth. However, grinding teeth regularly can extensively damage the tooth structure and increase the risk of jaw problems. Some of the common signs of bruxism include –

  • Tooth wear or fracture
  • Loosening of the tooth
  • Scalloped tongue
  • White ridges along the inner lining of the cheek
  • Notches on the gum line
  • Broken tooth fillings

Common symptoms of bruxism include –

  • A constant dull headache
  • Soreness of the jaw bone and muscles
  • Soreness of the back and neck
  • Tooth sensitivity
  • Pain and discomfort in the temporomandibular joint
  • Obstructive sleep apnea

Usually, a dentist detects the signs and symptoms of bruxism during a routine dental check-up. Treatment depends upon the type of dental ailment.

  • A sleep specialist usually treats obstructive sleep apnea. Typical treatment involves CPAP therapy or the use of an oral protective appliance.
  • Excessive tooth wear or fractures are treated with placement of a dental crown.
  • Tooth loss is compensated by implant therapy or bridge placement.
  • Malocclusions or bite corrections can be done by orthodontic therapy
  • A custom-fit night guard is fabricated that should be worn while sleeping. This device forms a barrier and helps to prevent tooth wear. Moreover, it relieves joint and muscle pain.


Tongue tension also referred to as tongue thrusting is a habit wherein the tongue protrudes forcibly through the upper front teeth. Often this activity is performed while swallowing and speaking. However, constant tongue thrusting can occur even when the tongue is at rest.

Often tongue thrusting develops as a secondary habitual adaptation. It can be due to structural changes in the mouth or presence of a primary parafunctional habit. Some of the common causes of tongue thrusting include –

  • Presence of large tongue
  • The steep angle of the jaw
  • Genetic malformation
  • Neurological or muscular abnormalities
  • Prolonged infantile suckling

Typical signs and symptoms of tongue thrusting include –

  • Forwardly placed upper front teeth
  • Poor facial development
  • Gum problems
  • Development of other parafunctional habits like mouth breathing or bruxism
  • Puckered lips especially while swallowing
  • High palatal arch
  • Development of a lisp while speaking

Often tongue thrusting develops as a consequence of thumb sucking. Children tend to develop the habit of tongue thrusting as a reflex to provide comfort and relaxation. Usually, they wean away from this habit by the age of 2-4 years. (3) A dentist commonly addresses the prolonged practice of tongue thrusting. As a treatment modality, the dentist may try different techniques listed below –

  • Positive re-enforcement often works well with children.
  • Breaking the habit by using dental appliances such as a bluegrass appliance or palatal crib which positions the tongue correctly in the mouth.
  • Myofunctional tongue exercises  are also an effective way of breaking the habit of tongue thrusting
  • Malocclusions can be treated by fixed orthodontic therapy

Thumb sucking

why do babies suck their thumb

Thumb sucking is a widespread oral habit that children develop for comfort and self-soothing. They usually grow out of this habit at the time of 2-3 years. However, prolonged thumb sucking can be destructive and difficult to manage. During this activity, the thumb exerts pressure against the front teeth and roof of the mouth. This condition leads to reshaping of the upper jaw.

As a result, the child develops a high narrow palate, forwardly placed upper front teeth, and an open bite. Additionally, the child may also develop the habit of tongue thrusting. To break the habit of thumb sucking is one of the hardest tasks. New parents need to understand the importance of dental visits for prevention of such situations. Some of the treatment modalities for thumb sucking usually involves –

  • Parental supervision – monitor the frequency of thumb sucking in the house. Often making the child aware of his habit by continually reminding him of the pattern may work to reduce the incidence of thumb sucking. (4)
  • Often with young toddlers, communicative exercises can help to grow him out of this habit. Talk to your child about quitting the habit. Reward the child when he consciously tries to stop the practice of thumb sucking.
  • For children who do not give up thumb sucking, thumb bandage can be useful. Thumb bandages help in providing an uncomfortable experience to the child every time he puts the thumb in the mouth. Constant discomfort during thumb sucking allows the child to refrain from this parafunctional habit.
  • Some chemical therapy may include the application of pepper powder on the thumb.

Mouth breathing

Typically, an individual breathes through the nose. Mouth breathing is a habit wherein a person inhales and exhales through the mouth. Breathing steadily through the mouth does not filter the air. Moreover, it dries the mouth. (5) Several causes can lead to mouth breathing. Some of them include –

  • Nasal congestion
  • Nasal obstruction and polyps
  • Obstruction of the paranasal sinuses
  • Deviated septum
  • Large adenoids
  • Adenoiditis with persistent rhinorrhea
  • High narrow palate
  • Excessive stress or anxiety

Usually, mouth breathers are not aware of their habit. However, typical symptoms can help to identify the parafunctional pattern. Symptoms of mouth breathing include –

  • Dry mouth and cracked lips
  • Snoring
  • Hoarseness of the voice
  • Bad breath
  • Feeling of tiredness during the day
  • Puckered lips
  • Dark circles under the eyes
  • Gingivitis and tooth decay
  • Frequent throat or ear infections

Usually, a dentist identifies the symptoms of mouth breathing during a routine dental check-up. The dentist may refer the patient to an ear, nose, and throat doctor for confirmation. Treatment of mouth breathing depends on the cause of the habit.

  • Medications can treat nasal obstructions like nasal decongestants, antihistamines, and steroidal nasal sprays.
  • Adhesive strips also referred to as nasal dilator, can be applied across the nose to increase airflow through the nose.
  • Mouth breathing caused by malocclusions of structural changes of the mouth can be corrected by orthodontic treatments like braces and orthognathic surgery.
  • Swollen adenoids or tonsils in children are often surgically removed to treat mouth breathing.

Lip biting

Lip biting is usually considered as a psychological behavior that is used as a coping mechanism during stress and anxiety. Some of the physical causes of lip biting include –

  • Misaligned teeth, for example, excessive overbite and underbite which may lead to crowding of the teeth
  • A temporomandibular joint disorder associated with muscular hyperactivity
  • Lip biting can also be a sign of body-focused repetitive behavior.

Usually, a person with a habit of lip biting may experience frequent episodes of painful sores on the lips, persistent inflammation of the lips associated with redness. (6) Like any other parafunctional habit, treatment of lip biting usually depends on the cause. Some of the treatment modalities are as follows –

  • People who develop lip biting as body-focused repetitive behavior are the best candidates for cognitive behavioral therapy. This procedure is a stepwise approach which helps the patient to modify their behavior by identifying the cause of lip biting. (7)

Another strategy for cognitive behavioral change is habit reversal therapy. In this procedure, the patient is made aware of the habit and trained to cope with a stressful situation using a different action that may not harm the tissues.

Social support for such patients can go a long way and help the person to overcome anxious and stressful situations. Relaxation therapies and stress reduction practices can add beneficial value. Additionally, medications like anti-depressants and serotonin inhibitors can be used to calm the patient.

Finger nail biting

Finger nail-biting is a widespread parafunctional habit among children. Moreover, it is the most destructive oral habit among all others. This is because nail-biting opens a direct portal for bacteria and germs to enter the mouth. (8) Typical signs and symptoms of nail-biting include –

  • Broken skin around the cuticle
  • Increased risk of viral infections like paronychia
  • Gingival injury
  • Malocclusions like anterior open bite and excessive overjet
  • Frequent stomach infections

Treatment of nail-biting usually includes behavioral modification or habit reversal therapy as used for lip biting. Additionally, applying clear and bitter-tasting nail polish to the nails may create an uncomfortable experience and help to refrain from the habit. For children, positive reinforcement works well and encourages the child to stop the habit of nail-biting.


Take away message

Parafunctional habits are prevalent among young adults and adolescents. It is also one of the most devastating oral habit. Usually, people develop parafunctional habits as behavioral reflex to comfort and relax during stressful situations. These activities are often performed as an involuntary action wherein the patient is unaware of the habit.

Some of the everyday parafunctional habits that involve the mouth, jaw, and tongue include mouth breathing, lip biting, finger nail biting, bruxism, and tongue thrusting. Treatment of the habits mentioned above usually depends upon the cause of the problem. Typically a dentist identifies the signs during a routine dental check-up.

It is essential to bring conscious awareness about the parafunctional habit to the patients. Moreover, seek professional help to treat the symptoms and prevent the parafunctional practice.


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