Statistics show that about one out of four dental patients have one of the oldest maladies known to man – bruxism or clenching.
Bruxism is the technical term for grinding of the teeth that soon removes critical portions of healthy enamel from the chewing surfaces of the teeth and may cause facial pain.
Clenching is a common variation of bruxism and involves non-purposeful closing of teeth in the chewing position – with an intensity of vertical movement of upto 14 times the normal .Only a few of these patients are aware of and treated for this condition before their dentition has been irreversibly destroyed requiring extensive restorative treatment or tooth extraction. Bruxism is a far more destructive process than caries. People who grind and clench, called bruxers, unintentionally bite down too hard at inappropriate times, such as in their sleep. In addition to grinding teeth, bruxers also may bite their fingernails, pencils and chew the inside of their cheek. People usually aren’t diagnosed with bruxism until it is too late because so many people don’t realize they have the habit. Others mistakenly believe that their teeth must touch at all times. Bruxism can easily be treated by a dentist.


People who have otherwise healthy teeth and gums can clench so often and so hard that over time their teeth become sensitive. They experience jaw pain, tense muscles and headaches along with excessive wear on their teeth. Forceful biting when not eating may cause the jaw to move out of proper balance. It can also cause stress fractures in the teeth.

Muscles that are stressed during the night set the stage for:
Migraine headaches
Tension type headaches
Sinus headaches
Allergy headaches
Premenstrual headaches Temporomandibular Joint (TMJ) pain
Pericranial (around the head) tenderness


When a person has bruxism, the tips of the teeth look flat. Teeth are worn down so much that the enamel is rubbed off, exposing the inside of the tooth which is called dentine. When exposed, dentine may become sensitive. Bruxers may experience pain in their temporomandibular joint (TMJ) -the jaw- which may manifest itself as popping and clicking. Women have a higher prevalence of bruxism possibly because they are more likely to experience tissue alterations in the jaw resulting from clenching and grinding. Tongue indentations are another sign of clenching.


Stress and certain personality types are at the root of bruxism. For as long as humankind has existed, bruxism has affected people with nervous tension. Anger, pain, and frustration can trigger bruxing. People who are aggressive, competitive, and hurried also may be at a greater risk for bruxism. Even if we do not wake with a headache, a slight increase of muscle contraction during the day can push already stressed muscles over the pain threshold and cause a headache.

Triggers vary from person to person. The following are some triggers that may spark off head pain episodes:
Daytime stress
Eye strain
Sinus infection
Caffeine withdrawal
Monosodium glutamate (MSG)
Changes in weather
Eyeglasses or headbands
Hormonal changes


During regular dental visits, the dentist automatically checks for physical signs of bruxism. If the dentist or patient notices signs of bruxism, the condition may be observed over several visits to be sure of the problem before recommending and starting therapy.

The objective of therapy is to get the bruxer to change behaviour by learning how to rest the tongue, teeth, and lips properly. When some people become aware of their problem, simply advising them to rest their tongue upward with teeth apart and lips shut may be enough to change their behaviour and relieve discomfort. Traditionally, a plastic mouth appliance, such as a NIGHT-GUARD or occlusal splint, that is worn to absorb the force of biting has been used. It forms a barrier between the top and bottom teeth to stop the grinding of the two arches. The nightguard receives the occlusal wear rather than the teeth. But its efficacy has been unpredictable because it is specific design addresses lateral movement (grinding), when it is the degree of intensity of vertical movement (clenching) which dictates severity of symptoms. A new method and device called the NTI-tss is more predictably effective (a simple modification of pre-existing concepts) – it suppresses clenching intensity by exploiting the nociceptive trigeminal inhibition reflex while preventing canine and posterior tooth occluding.

Therapy should be started as soon as the condition is diagnosed. This allows early non-invasive therapy instead of waiting until further tooth structure is destroyed, requiring more extensive care. This appliance can prevent future damage to the teeth and helps change the patient’s destructive behaviour and to relieve the tension-headache.

With daytime use, The NTI-tss system takes advantage of the naturally protective nociceptive trigeminal inhibition reflex which maintains relaxation the powerful temporalis muscles. It is the protective reflex experienced when biting down, expecting something soft, but encountering something hard.

How an NTI-tss works
Simple Demonstration of the efficacy of the NTI-tss device.


Begin by gently biting on the moon portion of your fingernail, using your central incisors. Only be forceful enough to create slight discomfort.


Now attempt to use the same amount of force, but this time bite with a canine tooth on the same spot of your fingernail as you did with the central incisors.

What happens?  Biting with the canine tooth is suddenly more painful than with the incisors… Why?

The incisor teeth are intended to not only incise food, but to be “hardness monitors” of what you’re biting into.  They are under your control and tell you if something will be to hard to chew.

The canine teeth are designed for grasping and pressing into what it is that you’re trying to hold on to.  The intensity of muscular activity created once the canine teeth have been engaged is under less voluntary control.  The message to the brain is: “We’ve opened our mouth to grab something and have caught it…hold on!”  The contacting canine teeth encourages jaw clenching!

Dentistry’s attempt at dealing with parafunctional jaw muscle activity (the most destructive of which is jaw clenching) has been to provide alterations of the biting surfaces of the teeth.


A full coverage splint, usually a thickness which mimics the intended space between the teeth when the jaw musculature is supposed to be at rest, provides both canine and posterior teeth contact, thereby allowing for perpetuation of parafunctional muscular activity.


By increasing the thickness of the splint, clenching intensity may be altered, depending on the amount of pressure applied to particular teeth. If contacts are “heavier” in the molar region, clenching intensity can be suppressed. If contacting is prevalent in the canine region, clenching is reflexive.


An anterior bite plane reduces parafunctional intensity of the masseters, and to a degree, the lateral pterygoids, but still provides canine contact for temporalis clenching.


The NTI-tss device reduces clenching intensity by exploiting the mechanisms of the incisor teeth and by avoiding the engagement of the canine and molar teeth when the jaw is centered (A), and when it is in excursive positions (B).