Cannabinoids Alleviate Symptoms of Bruxism

Bruxism

Bruxism is when you clench (tightly hold your top and bottom teeth together) or grind (slide your teeth back and forth over each other) your teeth.

Causes, incidence, and risk factors

People can clench and grind without being aware of it during both the day and night, although sleep-related bruxism is often the bigger problem because it is harder to control.

The cause of bruxism is not completely agreed upon, but daily stress may be the trigger in many people. Some people probably clench their teeth and never feel symptoms.  Whether or not bruxism causes pain and other problems may be a complicated mix of factors:

• How much stress you are under
• How long and tightly you clench and grind
• Whether your teeth are misaligned
• Your posture
• Your ability to relax
• Your diet
• Your sleeping habits
• Each person is probably different.

Causes

Bruxism is a habit rather than a reflex chewing activity.  Reflex activities happen reliably in response to a stimulus, without involvement of subconscious brain activity.  Chewing and clenching are complex neuromuscular activities that can be controlled either by subconscious processes or by conscious processes within the brain.  During sleep, (and for some during waking hours while conscious attention is distracted) subconscious processes can run unchecked, allowing bruxism to occur.

Some bruxism activity is rhythmic with bite force pulses of tenths of a second (like chewing), and some has a longer bite force pulses of 1 to 30 seconds (clenching).  Researchers classify bruxism as "a habitual behavior, and a sleep disorder."

The etiology of problematic bruxism can be quite varied, from allergic reactions or medical ailments, to trauma (such as a car crash) to a period of unusual stress, but once bruxism becomes a habit, the original stimulus can be removed without ending the habit.  Certain medical conditions can trigger bruxism, including digestive ailments and anxiety.

Associated factors

The following factors are associated with bruxism:
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
Relatively high levels of consumption of caffeinated drinks and foods, such as coffee, colas, and chocolate High levels of blood alcohol
Smoking
High levels of anxiety, stress,  work-related stress,  irregular work shifts,  stressful profession and ineffective coping strategies.
Drug use, such as SSRIs and stimulants  including:   methylenedioxymethamphetamine (ecstasy), methylenedioxyamphetamine (MDA), methylphenidate and other amphetamines, including those taken for medical reasons.
Hypersensitivity of the dopamine receptors in the brain.
Frequent use of GHB and similar GABA-inducing analogues such as Phenibut
Disorders such as Huntington's and Parkinson's diseases
Obsessive Compulsive Disorder

Signs and tests

An examination can rule out other disorders that may cause similar jaw pain or ear pain, including:
Dental disorders
Ear disorders such as ear infections
Problems with the temporomandibular joint (TMJ)
You may have a history of significant stress and tension.

Eventually,  bruxism with lateral movements shortens and blunts the teeth being ground and may lead to myofascial muscle pain, temporomandibular joint dysfunction and headaches.  If enough enamel has been abraded, the softer dentin will be exposed, and abrasion will accelerate.  This opens the possibility of dental decay and tooth fracture, and in some people, gum recession.  Early intervention by a dentist is advisable.  In severe, chronic cases, bruxism can lead to arthritis of the temporomandibular joints.  The jaw clenching that is often part of bruxism can be an unconscious neuromuscular daytime activity.  There is no recognized TMJ specialty in dentistry.  See a dentist immediately if you are having trouble eating or opening your mouth.  Keep in mind that a wide variety of possible conditions can cause TMJ symptoms, from arthritis to whiplash injuries.  Therefore, see your dentist for a full evaluation if self-care measures do not help within several weeks.

Grinding and clenching does not fall clearly into one medical disciplines.  For a massage-based approach, look for a massage therapist trained in trigger point therapy, neuromuscular therapy, or clinical massage.
Dentists who have more experience in evaluating and treating TMJ disorders will typically take x-rays and prescribe a mouth guard.  Surgery is now considered a last resort for TMJ.

Symptoms

Patients may present with a variety of symptoms, including:
 Anxiety, stress, and tension
 Depression
 Earache
 Eating disorders
 Headaches
 Migraines
 Loose teeth
 Tinnitus
 Gum recession
 Neck pain
 Insomnia
 Sore or painful jaw

Symptoms

Clenching the teeth puts pressure on the muscles, tissues, and other structures around your jaw. The symptoms can cause temporomandibular joint problems (TMJ).
Grinding can wear down your teeth.  Grinding can be noisy enough at night to bother sleeping partners.
Most people are not aware of their bruxism. Only an estimated 5% go on to develop symptoms, such as jaw pain and headaches, which prompt treatment.[6] A sleeping partner or parent may notice the behavior first, although sufferers may notice pain symptoms without understanding the cause.
Bruxism can result in occlusal trauma, the abnormal wear patterns of the occlusal surface, abfractions and fractures in the teeth. Over time, dental damage increases. Bruxism is the leading cause of occlusal trauma and a significant cause of tooth lossand gum recession. Bruxism can be loud enough to wake a sleeping partner. Some individuals clench without significant lateral movements.

In a typical case involving lateral motion, the canines and incisors of the opposing arches are moved against each other laterally, i.e., with a side-to-side action, by the medial pterygoid muscles that lie medial to the temporomandibular joints bilaterally. This movement abrades tooth structure and can lead to the wearing down of the incisal edges of the teeth.  People with bruxism may also grind their posterior teeth, which will wear down the cusps of the occlusal surface.  Most (but not all) bruxism includes clenching force provided by masseter and temporalis muscle groups, but some bruxers clench and grind front teeth only, which involves neither masseter nor temporalis muscle groups.  Teeth hollowed by previous decay (caries), or dental drilling, may collapse from bruxism's cyclic pressures.

Treatment

The goals of treatment are to reduce pain, prevent permanent damage to the teeth, and reduce clenching as much as possible.
To help relieve pain, there are many self-care steps you can take at home. For example:

• Apply ice or wet heat to sore jaw muscles. Either can have a beneficial effect.
• Avoid eating hard foods like nuts, candies, steak.
• Drink plenty of water every day.
• Get plenty of sleep.
• Learn physical therapy stretching exercises to help restore a normal balance to the action of the muscles and joints on each side of the head.
• Massage the muscles of the neck, shoulders, and face. Search carefully for small, painful nodules called trigger points that can cause pain throughout the head and face.
• Relax your face and jaw muscles throughout the day. The goal is to make facial relaxation a habit.
• Try to reduce your daily stress and learn relaxation techniques.

Treatment

If disagnosed early, finding and eliminating the original cause(s) may cure bruxism. Later on, habitual bruxism can be treated by habit-modification.  Treating associated factors can reduce or eliminate the behavior in cases where bruxism has not become habitual.

Dental guards and splints

A dental guard or splint can reduce tooth abrasion. Dental guards are typically made of plastic and fit over some or all of upper and/or lower teeth. The guard protects the teeth from abrasion and can reduce muscle strain by allowing the upper and lower jaw to move easily with respect to each other. Treatment goals include: constraining the bruxing pattern to avoid damage to the temporomandibular joints; stabilizing the occlusion by minimizing gradual changes to the positions of the teeth, preventing tooth damage and revealing the extent and patterns of bruxism through examination of the markings on the splint's surface. A dental guard is typically worn during every night's sleep on a long-term basis. Dental guards do not cure the condition.
A repositioning splint is designed to change the patient's occlusion, or bite.

To prevent damage to the teeth, mouth guards or appliances (splints) have been used since the 1930s to treat teeth grinding, clenching, and TMJ disorders.  A splint may help protect the teeth from the pressure of clenching.

A splint may also help reduce clenching, but some people find that it makes their clenching worse.  In others, the symptoms go away as long as they use the splint, but pain returns when they stop or the splint loses its effectiveness over time.
There are many different types of splints.  Some fit over the top teeth, some on the bottom.  They may be designed to keep your jaw in a more relaxed position or provide some other function.  If one type does not work, another may.

For example, a splint called the NTI-tss fits over just the front teeth.  The idea is to keep all of your back teeth (molars) completely separated, under the theory that most clenching is done on these back teeth. With the NTI, the only contact is between the splint and a bottom front tooth.

As a next phase after splint therapy, orthodontic adjustment of the bite pattern may help some people. Surgery is considered a last resort.
Finally, there have been many approaches to try to help people unlearn their clenching behaviors.  These are more successful for daytime clenching, since nighttime clenching cannot be consciously stopped.
In some people, just relaxing and modifying daytime behavior is enough to reduce nighttime bruxism. Methods to directly modify nighttime clenching have not been well studied.  They include biofeedback devices, self-hypnosis, and other alternative therapies.
"Bedside" EMG units are similar to those used by sleep labs.  These units pick up their signals from facial muscles through wires connecting the bedside unit to electrodes that are adhesively attached to the user's face.  TENS electrodes or ECG electrodes may be used.
A biofeedback headband may be used in silent mode to record the total number of clenching incidents and the total clenching time each night.  These two numbers easily distinguish clenching from rhythmic grinding and allow dentists to quantify severity levels.  Biofeedback headbands do not require adhesive electrodes or wires attached to the face.  They do not record the exact time, duration, and strength of each clenching incident as bedside EMG monitors do.
Bedside EMG units and biofeedback headbands may be used either as a diagnosis measurement or in biofeedback mode as a treatment to help patients break their bruxism habit.
"Disposable" EMG monitors adhesively mount to the side of the face over the masseter muscle.  They monitor one night and provide a single-digit measure of bruxism severity.

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 , a known treatment for gastric problems, and gastric problems such as acid reflux are known to increase bruxism.

Prevention

Stress reduction and anxiety management may reduce bruxism in people prone to the condition.

Other Treatments

Botox
Botulinum toxin (Botox) can lessen bruxism's effects, though serious side-effects (including death) are possible.  In extremely dilute form Botox is injected to weaken (partially paralyze) muscles and has been used extensively in cosmetic procedures to 'relax' the muscles of the face.  Facially injected Botox has been found to propagate into the brains of test animals, and the U.S. Food and Drug Administration (FDA) announced a safety review of Botox and similar drugs.  Less than one microgram of ingested or inhaled botulinum toxin is sufficient to kill an adult human.

Botox was originally developed for use in treating strabismus (misalignment of eyes), during trials of which its effects on wrinkles in the eye area were discovered.  It was, and continues to be, used to treat diseases of muscle spasticity such as strabismus, blepharospasm (eyelid spasm), andtorticollis (wry neck).  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 weakens the muscle enough to reduce the effects of grinding and clenching, but not so much as to prevent proper use of the muscle.  Although the intent of Botox injections is for the Botox to go into the muscle and not into the rest of the body, it has been shown that some percentage of injected Botox  winds up in the vascular system and migrates to other parts of the body.  Botox treatment typically involves five or six injections into the masseter muscles.  It takes a few minutes per side, and the patient starts feeling the effects the next day.  Occasionally, bruising can occur, but this is quite rare.  Injections must be repeated more than once per year, and the risk factor of spread of the botulinum toxin is compounded by this repetition.

The optimal dose of Botox must be determined for each person as some people have stronger muscles that need more Botox.  This is done over a few touch-up visits with the physician. The effects last for about three months.  The muscles do atrophy, however, so after a few rounds of treatment, it is usually possible either to decrease the dose or increase the interval between treatments.

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1. Reviewed by: Jack D Rosenberg, DDS, Advanced Dental Care, Palm Beach Gardens, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, M.D., MHA, Medical Director, A.D.A.M., Inc.