What is Bruxism?

Definition: According to AAOFP bruxism is a diurnal or nocturnal parafunctional activity including clenching, bracing, gnashing and grinding of the teeth.

Ramfjord 1996: As a habitual grinding of teeth where individual is not chewing or swallowing.

Rubina 1986: Indicates a nonfunctional contact of teeth which may include clenching, gnashing, grinding and tapping of teeth.

The term Bruxism is derived from the Greek word “brychein” meaning tooth grinding. And it was first introduced in 1931 officially.

Bruxism is a condition in which the person unknowingly Grinds or clenches or gnashes their teeth against each other, which is divided into two types –

  • Awake Bruxism (diurnal)- clench your teeth while being awake or during the day
  • Sleep Bruxism (nocturnal)- clench your teeth while sleeping, which is the subconscious grinding of teeth characterized by rhythmic patterns of masseter EMG activity.

In general Bruxism is regarded as forcible clenching or grinding of the dentition or a combination of both. The term Bruxism has been coined from the Greek word – “brychein” meaning tooth grinding. It was first introduced in 1931 to describe the involuntary, excessive grinding, clenching or rubbing of the teeth during nonfunctional movements of the masticatory system. The International Classification of Sleep Disorders reclassified bruxism in 2005 as a sleep-related movement disorder changing it from the previous classification as parasomnia.

The reasons for each type of Bruxism is different, while sleep bruxism is associated with any underlying sleep related disorder, awake bruxism is related to conditions like Temporomandibular disorders, Stress, Anxiety etc.

Occasional teeth grinding is common in most people which does not cause harm to teeth or underlying structures, but when teeth grinding occurs regularly it can result in loss of tooth structure which should be intervened. It is a disorder of neuromuscular activity which may affect any element of the masticatory system.

Symptoms of Bruxism:

  • Bruxism being a neuromuscular disorder the patient tends to have pain in the muscles of mastication which can be either local or regional.
  • Attrition of Front and Back Teeth
  • Pain tends to increase while chewing and other functional movements.
  • Mouth opening is restricted in some cases
  • Pain and tenderness on palpation of the muscles is seen
  • Teeth are worn out and occlusal cusps are lost with the occlusal surface becoming flat
  • Pain in the TMJ or TMD is seen in some chronic cases
  • 90% of the population tend to show one or the other form of Bruxism
  • Incidence is highest in teens and in their 40’s
  • Females tend to be more than males

Causes of Bruxism:

Bruxism is said to occur in about 90% of the population, while some studies suggest that it affects 8% of adults, 14% of the children and 10-12% of adolescents. The incidence of bruxism is highest in teens and forties. In reference to Sex – Females are known to be more prone to Bruxism as compared to Males.

Causes of Bruxism to be put in a single sentence is that it is Multi Factorial, in simple terms it means that there are multiple causes for Bruxism. Most common causes are any stimulation to the neuromuscular system of the mandible can lead to bruxism at the subconscious level.

  • Occlusal interference or Malocclusion is also a known cause of Bruxism where the patient subconsciously attempts to attain self-equilibrium of occlusion by grinding his or her teeth together leading to bruxism. A force of as little as 1.5 grams is detectable by teeth and any item less about 8-10 microns is detectable by some individuals which anything more than 60 microns is detectable by all.
  • Mouth breathing
  • Habitual Snoring
  • Upper Airway obstruction with obstructive sleep apnea are seen in Sleep Bruxism patients along with other conditions such as Asthma and Respiratory infection.
  • Tonsillar Hypertrophy which can lead to upper airway obstruction is seen directly linked to Bruxism
  • Stress – Emotional or Physical stress can lead to bruxism
  • Sleep Disorders – Patients with sleep disorders have been known to have bruxism.
  • Alcoholism has been found to be an aggravating factor
  • Certain Medication has also been found to aggravate bruxism
  • Centric and Eccentric bruxism are expressions of increased muscle tonus
  • Discrepancy between Centric Relation and Centric Occlusion is the most common trigger factor for bruxism
  • Interference in the balancing side and working side are known to be trigger factors for bruxism
  • Any Disharmony between the masticatory system and the functional parts
  • Emotional influence on the Muscles of mastication can lead to clenching of teeth

On the whole, a relationship between local, environmental, and emotional factors can lead to Bruxism.

Clinical Features of Bruxism:

Apart from the obvious Grounding and Tapping sounds heard by the patient and the ones around then we can also see ulcers or trauma to the soft tissue in the occlusal line, Ridging on the buccal mucosa opposite to the molar teeth is also seen in most cases.

Occlusal Trauma: Pain in the Lower jaw usually early in the morning

Occlusal Wear of the tooth structure: Occlusal surfaces of the posterior teeth have an atypical shiny rounded surface, It can lead to Sensitivity, yellowish discoloration of the tooth due to loss of Enamel and exposure of Dentin. Fracture of tooth and in some cases pulpal exposure is seen. Wear facets are seen in the Molars.

Muscular Pain: Pain or discomfort in the masseter and lateral pterygoid muscles in the morning is experienced. There is hypertrophy of the masseter muscle seen in Chronic Bruxism patients.

Headache: Unilateral headache is felt on one side of the head, it is also termed by some patients as muscular contraction type headache.

TMJ: Clicking, restriction of mandibular movements, deviation of chin, Crepitation and pain on opening is seen on one side.

How to check if you Grind your Teeth?

First let us know what exactly Clenching and Grinding of Teeth is –

One Simple observation which you can do at your home is, to check if you are having any ulcer or a Occlusal line on your cheek at the Occlusal Plane. It is called as Linea Alba and the cheek biting habit can be controlled by a Removable habit breaking appliance.

Clenching: It is the forcible closure of the upper and lower dentition in a static (no movement) relationship of the mandible and maxilla. It is seen with either maximum intercuspation or in an eccentric position.

Grinding of Teeth: It is the forcible closure of the upper and lower teeth in a dynamic (moving) maxillo-mandibular relationship, the mandible moves in various excursive positions leading to loss of tooth structure.

Brux Checker: It is a 0.1 mm thick colored coating on one side which is used to register the occlusal interferences through abrasion on the foil surface thus diagnosing Bruxism.

Treatment of Bruxism:

There are multiple modes of treatment of Bruxism which depends on the type, duration and extent of damage caused to the teeth. The main aim in the treatment of Bruxism is to Redistribute the Occlusal forces and relieve stress from the Masticatory muscles.

Night Guard for Bruxism

Occlusal Splints, Bite / Night Guard and Occlusal Adjustments: These are the most common treatment followed by Dentists which help in correcting Bruxism in most cases. This method is aimed at correcting or reprogramming the existing muscular pattern to redistribute masticatory forces to help stop Bruxism. Soft Splints are advised without occlusal surface to encourage movement of mandible in all planes. Occlusal Adjustments also does the same, where you identify the points which are causing interference and Grind it to let the mandible move freely in all planes.

The use of Inter occlusal appliance has helped in improvements of Symptoms with the decrease in nocturnal masseter activity. A Study has showed that due to decrease in Masseter activity there was an 80-90% improvement in symptoms.

Correction of Malocclusion: Occlusal Correction of Malocclusions such as Class II, Class III which are seen to be the reason for Bruxism in some cases when corrected can help in controlling Bruxism in such patients. Habit breaking appliances can also be used in cases where Tongue thirsting or Thumb sucking habits are the reason for Malocclusion which in turn leads to Bruxism.

Drugs or Medicines: 

  • Placebos are found to have great effect it making the patients rectify their problem themselves.
  • Local Anesthetics for TMJ Pain
  • Diazepam to correct Anxiety and alteration of sleep arousal
  • Muscle Relaxants to de-stress the muscle tissue and reduce the force applied on the Jaws
  • Depending on the cause in some cases Antidepressants are also prescribed.