Exodontia.Info
Bruxism / Tooth Grinding
Bruxism (from the Greek βρυγμός "gnashing of
teeth") is characterized by the grinding of the teeth and
is typically accompanied by the clenching of the jaw.

It is an
oral para-functional activity that occurs in most
humans at some time in their lives.

In most people,
bruxism is mild enough not to be a
health problem.  While
bruxism may be a diurnal
(during the day) or
nocturnal (during the night) activity,
it is
bruxism during sleep that causes the majority of
health issues and can even occur during short naps.

Bruxism is one of the most common sleep disorders.
Photo of Bruxism-related Tooth Damage
Causes

Bruxism is more accurately classified as a habit.

Some
bruxism activity is rhythmic (like chewing) though some activity is sustained
(clenching).  Researchers classify
bruxism as "a habitual behaviour and a sleep
disorder
".

Most
bruxists are not aware of their bruxism and only 5% go on to develop
symptoms, such as jaw pain and headaches, which will require treatment.  In many
cases, a sleeping partner / parent will notice the
bruxism before the person
experiencing the problem becomes aware of it.

Bruxism can result in abnormal wear patterns of the biting surfaces of the teeth,
abfractions  and fractures in the teeth.  This type of damage is categorised as a
sign of
occlusal trauma.

Over time, dental damage will usually occur.  
Bruxism is the leading cause of
occlusal trauma and a significant cause of tooth loss and gum recession.

In a typical case, the canines and incisors of the opposing jaws are moved against
each other laterally, i.e. with a side-to-side action, by the chewing muscles that lie
on the inside of the jaw joints (
medial pterygoid muscles). This movement abrades
tooth structure and can lead to the wearing down of the biting (
incisal) edges of the
teeth.  People with
bruxism may also grind their back (posterior) teeth, which will
wear down the cusps of the biting surface of the teeth.

Bruxism can be loud enough to wake a sleeping partner.  Some individuals will
clench the jaw without significant lateral movements.  Teeth hollowed by previous
decay (
caries) or dental drilling, may collapse, as the cyclic pressure exerted by
bruxism is extremely taxing on the tooth structure.
Symptoms

Patients may present with a variety of symptoms, including:

  • Anxiety, stress and tension
  • Depression
  • Earache
  • Eating disorders
  • Headache
  • Insomnia
  • Sore / painful jaw

Associated Factors

The following factors are associated with bruxism:

  • High levels of anxiety, stress, work-related stress, irregular work shifts,
    stressful profession and ineffective coping strategies
  • Relatively high levels of consumption of caffeinated drinks and foods, such as
    coffee, colas, and chocolate
  • High levels of blood alcohol
  • Smoking
  • Disturbed sleep patterns and other sleep disorders (obstructive sleep apnea,
    hypopnea, snoring, moderate daytime sleepiness)
  • Malocclusion, in which the upper and lower teeth occlude in a disharmonic
    way, e.g., through premature contact of back teeth
  • Drug use, such as the newer antidepressants (SSRI’s) and stimulants (such as
    ecstasy, MDA and amphetamines)
  • Hypersensitivity of the dopamine receptors in the brain
  • GHB and similar drugs when taken with high frequency
  • Disorders such as Huntington's and Parkinson's diseases
  • Obsessive Compulsive Disorder

Treatment

Bruxism may be reduced or even eliminated when the associated factors, e.g.,
sleep disorders, are treated successfully.

Although there is no single accepted cure for
bruxism, there are a number of
treatments available.

  • Mouthguards & Splints
  • Habit Breakers
  • Nociceptive Trigeminal Inhibitor
  • Biofeedback
  • Cognitive Behavioural Therapy
  • Botox
  • Dietary Supplements


Mouthguards & Splints

Ongoing management of bruxism is based on minimising the abrasion of tooth
surfaces by the wearing of an acrylic / soft plastic dental guard or splint (
Bite
Raising Appliances
, BRA’s), designed to the shape of an individual's upper or lower
teeth.  These are made by dentists.

BRA’s are thought to work in the following ways:

  • constraining bruxism so that damage to the TMJ joints is prevented
  • stabilisation of the occlusion by minimising the gradual changes to the positions
    of the teeth that typically occur with bruxism
  • prevention of tooth damage and
  • assist a dentist to judge - in broad terms - the extent and patterns of bruxism
    through examination of the physical indentations on the surface of the splint.

A
BRA is typically worn on a long-term basis every night.

Although
BRA’s are a first response to bruxism, they do not in fact help cure it.  
Professional treatment is recommended to ensure proper fit, make ongoing
adjustments as needed and check that the
occlusion (bite) has remained stable.  
Monitoring of the
BRA is suggested at each dental visit.

Another type of device sometimes given to a
bruxist is a repositioning splint.

A
repositioning splint may look similar to a traditional BRA but is designed to
change the bite (
occlusion) of the patient.  Scientific studies of these devices
generally showed no benefit over more conservative therapies.

Useful Articles:

Cochrane Database of Systematic Reviews 2007.  Occlusal splints for treating
sleep bruxism (tooth grinding).

Medscape Medical News
Habit Breakers

This is a development of a BRA's.  These are worn mainly at night.  When the
patient clenches, the metal 'projections' impinge on the roof of the mouth.  This
would wake or disturb the sleep of the clencher and would theorectically break the
habit (eventually).
Photos of Mouth Guards / Splints / BRA's
Nociceptive Trigeminal Inhibitor Device / Appliance

The NTI appliance fits on top of the teeth and alters the angle at which the jaw
opens, by covering only the front teeth and preventing the molars from coming into
contact with each other, thus limiting the contraction of the
temporalis muscle.  
When the grinding starts in the night, the pressure which is applied to the
incisors
can, it is claimed, send an alarm signal to the brain.

The
NTI device must be fitted by a dentist.

The efficacy of such devices is debated.  Some writers propose that irreversible
complications can result from the long-term use of mouthguards and repositioning
splints.


Useful Articles:

Evidence Based Dentistry 2009.  The NTI-tss device may be used successfully in
the management of bruxism & TMD

Bio Med Central Oral Health 2008.  The NTI-tss device for the therapy of bruxism,
temporomandibular disorders and headache – Where do we stand. A qualitative
systematic review of the literature.


Useful Websites:

Wikipedia

Nociceptive Trigeminal Inhibition-Tension Suppresion System

Nociceptive Trigeminal Inhibition Tension Suppression System - How Does It Work
Nociceptive Trigeminal Inhibitor-Tension Suppression System Appliance
(NTI-tss) Appliance
Nociceptive Trigeminal Inhibitor-Tension Suppression System Appliance (NTI-tss)
Appliance
being worn
Bio-Feedback

Various bio-feedback devices are currently available and effectiveness varies
significantly depending on whether the
bio-feedback is used only during waking
hours or during sleep as well.

Many authorities remain unconvinced of the efficacy of 'daytime-only'
bio-feedback.

The efficacy of
bio-feedback delivered during sleep can depend strongly on
daytime training, which is used to establish a
Pavlovian response to the bio-
feedback
signal that persists during sleep.

Useful Websites:

GrindAlert by BruxCare

SleepGuard

GrindCare

Taste Bio-Feedback


Cognitive Behavioural Therapy

Cognitive Behavioural Therapy (CBT) aims to help the patient to manage their
problems by changing how they think and act.

CBT encourages the patient to talk about:

  • how they think about themselves, the world and other people
  • how what the patient does affects their thoughts and feelings

By talking about these things,
CBT can help the patient to change how the patient
thinks (‘
cognitive’) and what the patient does (‘behaviour’), which can help the
patient feel better about life.

Useful Websites:

Wikipedia

Royal College of Psychiatrists

NHS Choices

Patient UK


Botox

Botulinum toxin (Botox) can be successful in lessening effects of bruxism.

Bruxism can also be regarded as a disorder of repetitive, unconscious contraction
of the
masseter muscle (the large muscle that moves the jaw).  In the treatment of
bruxism, Botox works to weaken the muscle enough to reduce the effects of
grinding and clenching but not so much as to prevent proper use of the muscle.  
Injections must be repeated more than once per year.

The symptoms that can be helped by this procedure include:

  • Grinding and clenching
  • Morning jaw soreness
  • TMJ pain
  • Muscle tension throughout the day
  • Migraines triggered by clenching
  • Neck pain and stiffness triggered by clenching

The effects last for about three months.  The muscles wither (
atrophy), however,
so after a few rounds of treatment, it is usually possible either to decrease the
dose or increase the interval between treatments.

Other authorities caution that
Botox should only be used for temporary relief for
severe cases and should be followed by diagnosis and treatment to prevent future
bruxism or jaw clenching, suggesting that prolonged use of Botox can lead to
permanent damage to the jaw muscle.

Useful Website:

The Daily Mail, March 2009 - How to stop teeth-grinding ... with a little help from
Botox


Dietary Supplements

There is anecdotal evidence that suggests taking certain combinations of dietary
supplements may alleviate
bruxism; pantothenic acid, magnesium and calcium
are mentioned on dietary supplement websites.

Calcium is known to be a treatment for gastric problems, and gastric problems
such as acid reflux are known to increase
bruxism.  Placing whole cloves at night
inside the mouth is suggested to have an effect on the jaw's muscle by relaxing it,
yet evidence of this remains largely anecdotal without future research.


Useful Articles:

American Dental Association 2005.  Do You Grind Your Teeth?

Cochrane Database of Systematic Reviews 2008.  Occlusal splints for treating
sleep bruxism (tooth grinding)

Vital Summer 2011.  Raising awareness of bruxism

American Academy of Oral Medicine 2008.  Patient Information Sheet.  Tooth
Clenching or Grinding


Useful Websites:

Wikipedia

WebMD

The Bruxism Association

Bruxism (Teeth Clenching or Grinding) Advice, Links, Resources

MedicineNet.com

BBC News - Why are we grinding our teeth so much?

BBC Case Notes – The Jaw (also covers bruxism)

Health-Cares.net

Bruxism Ireland

The Times, March 2009 - Q&A: How to deal with grinding teeth.

Teeth Grinding Forum

NHS Choices - Teeth Grinding (Grinding)
Photos of Habit Breakers (my thanks to Derek Lucas for these photos)
Last Updated 1st November 2011