Chapter 5


Let's go back to the fist clenching example again. Certainly, there are degrees of fist clenching. Simply curling your fingers is the slightest degree of fist clenching, and squeezing as hard as possible is the most severe degree of fist clenching. Assume that someone has developed a habit of clenching their fist during sleep and during periods of stress throughout the day and is completely unaware of it. Imagine we are the town specialists in forearm ache and an otherwise healthy 35-year-old female comes to us with a daily forearm ache. We suggest to the patient that perhaps she is a fist-clencher. Our patient confidently denies that she does any such thing because she's having a terrible forearm ache at that moment, and she's not making a fist. We know, however, that muscles can become very painful long after an exercise has been completed. How can we keep this patient from clenching her fist? How about giving our chronic fist clencher a billiard ball to hold on to? Would that make her forearm muscles relax? That probably depends on how severe a fist clencher she is. She may stop it at first, but then may get used to it and then clench the billiard ball anyway. How about using a tennis ball? Perhaps the rhythmic squeezing may keep her forearm from burning, but she'll still be fatigued, and her arm will still hurt. Our treatments, so far, have merely modified the fist clencher's ability to clench, but haven't prevented the clenching. But what if we were to tape her outstretched fingers to a ping-pong paddle? She couldn't make a fist or curl her fingers to begin with! Soon after our paddle treatment, our patient's forearm no longer hurts. We leave the ping-pong paddle on for a few weeks until our patient learns not to clench her fist. We've been allowing her to remove the paddle whenever she needs to use her hand, but she re-applies the paddle at all other times. Our patient now tells us that without the paddle, she is very much aware of her fist clenching and can catch herself before she can do any real damage. We recommend that she wear her paddle during times of particular intensity during the day (like a scary movie) and to continue to wear the paddle during sleep, indefinitely. She readily agrees and tells us that whenever she has forgotten to wear her paddle to bed, she has awakened with a stiff and sore arm.

O.K., so now it's time to let you in on the little secret. Research has shown an association between intense chronic temporalis contraction and chronic headaches. When the temporalis contracts, it closes the jaw until the teeth touch (remember, the temporalis is really a jaw muscle, located on the scalp). Intense continual contraction of the temporalis (teeth touching or clenching) develops myofascial dysfunction of the temporalis, displayed as chronic headaches.  It may surprise you to know that in the daytime, teeth should never be touching (i.e., temporalis contracting) except when eating! So here is where it gets interesting. Everybody, when asleep and dreaming, contracts their temporalis muscles from time to time. That is to say, it is normal to clench your teeth while asleep. What sets chronic headache  patients apart from the pain-free crowd is not that they are teeth clenchers (because everybody is), but rather they are more intense at it than others.

Doctors are trained to look for abnormalities. They will run a series of tests, looking for something abnormal to pop up. Once they find something wrong on your x-ray, MRI, blood work, etc., they can look in a book and find a description of the usual presentation of that abnormality. What I'm describing, however, is the opposite. Temporalis contraction is a normal function, but it's the presentation that is unusual. No wonder our doctors haven't found anything wrong with us. Here we've got all these wild symptoms and nothing to show for it.  How is your physician supposed to know that a "normal" activity can result in such abnormal symptoms?

Now here is the most interesting part.  Within every muscle, there exists tiny thread-like organs called "muscle spindles", or "spindle fibers".  The spindles are believed to be stretch receptors, where upon being stretched, the spindle relays a message to the central nervous system, which is in turn is relayed back to the "intrafusal fibers" of the spindle (meaning inside the spindle).  The intrafusal fibers then contact, thereby encouraging the extrafusal (or outside the spindle) fibers to contract.  The end result is a muscle which slightly shortens in response to be stretched.   Now get this…research has now shown that in the chronic tension-type headache patient, those intrafusal fibers of the neck and scalp within are constantly in  a state of tension, or contraction…without purpose (hey, that's dysfunctional!).   Additionally, the division of the central nervous system which maintains the intrafusal fiber contraction is now strongly believed to be the sympathetic nervous system.  You know the sympathetic nervous system.  It's the one that controls the "fight or flight" response to stress or threat.   So how does the tension-type headache patient respond to stress?  They feel a headache coming on.  Are their scalp muscles contracting?  No.  Are they getting increased input to the intrafusal fibers from the sympathetic nervous system?  Yes.  And what if the input was enough to make the chronically contracted spindle actually contort on itself?  Yeow.  That would be like a muscle cramp, wouldn't it?  Let's see, intense and debilitating pain from somewhere from the neck up, perhaps  intense enough that you become nauseous and sensitive to light, in the absence of any identifiable disease.  We've just described common migraine.  Perhaps if the musculature hadn't experience such intense contractions during sleep, these spindle fibers wouldn't be so susceptible to spasm…but I'm getting ahead of myself.

And you're thinking, "Yeah, right. My headaches are due to sinuses , or red wine, or my neck vertebrae, etc..." Well, you're partially right (I'll be getting to those details later). Hundreds of patients who have experienced every possible treatment imaginable are now convinced that they were chronic, intense jaw clenchers during sleep and had absolutely no awareness of it!  Some of their comments appear throughout this book.

One method to determine if intense jaw clenching (i.e., chronic, intense temporalis contraction) is a source of your headaches is to firmly press on your temporalis muscle.  Here's what you do.  First, press on your forehead at the hairline, right in the middle.  Don't be too gentle. You should be able to press pretty hard not feel much (or any) pain or soreness.  This is your control so that you know what normal is supposed to feel like.  Now you press on several spots throughout your temporal area, very firmly.   When I do this to my patients, they advise me that it obviously hurts because I'm pressing so hard. Wrong. There should be no pain at all. It should feel the same as when you press on your forehead at the hairline. Ask somebody who never has headaches to do this on themselves...they'll barely hurt at all. If you can find some sore spots, good for you; keep reading!

Consider the person who, instead of a painful forearm, feels pain and pressure on the side or sides of the head. Could it be that the temporalis muscle is painful (i.e., headache) because intense due to intense contraction during sleep? During the daytime, even the slightest touching of the teeth requires contraction of the temporalis muscles (just like raising your arm requires contraction of the shoulder muscle). I used to think that since teeth seem to fit together pretty well, they should be together, right? Wrong. Although it seems harmless enough, daytime teeth clenching (usually during stressful events) acts as an irritation to pre-existing dysfunctional temporalis muscles (caused by the nighttime clenching). Remember, when your hand is at rest, it should not be gripping an object; and when you're not chewing food, your jaw should be at rest, so your teeth should not be touching. Simply allowing the teeth to touch requires a continual contraction of the temporalis muscle. Once the teeth are in contact, any degree of intensity of temporalis contraction and resultant clenching is likely to occur, without that person's awareness. The episodic and often severe continual contraction of the temporalis muscle during sleep results in its dysfunctional state, which may not be painful until a later time. This is one reason why some medical studies find no increase in muscle activity during a headache.  Another example of this delayed muscle pain occurs in the weekend athlete who plays a hard game of football on Saturday, and whose muscles are sore and painful on Monday.

What can we do for these intense nighttime jaw clenchers? What if we placed the hard, acrylic, flat-plane TMJ splint in their mouths? Would that make their temporalis muscles relax? The answer probably depends on the intensity of their jaw clenching habit compared to their teeth grinding habit.  They are entirely two different things.  Certainly, teeth are protected from severe grinding, but jaw clenching is another story.  These patients may lessen the intensity of their clenching at first, but once they get used to the splint, they clench into it anyway, sometimes harder! That's how TMJ treatment gets a bad reputation...clenching patients sometimes get worse. Some doctors will try to make a splint out of a soft plastic, but that simply allows these patients to chew into the splint, thus maintaining their muscular fatigue and headache.

Just as the remedy for the fist clencher was to create a situation in which her fingers couldn't curl, the remedy for the jaw clencher is to prevent the back teeth from touching each other or from touching objects that are sandwiched between them (like the splint). Essentially, an 'air-space' should exist between the upper and lower teeth when not chewing.  Remember how to feel for the temporalis muscle? It is difficult to sense the bulging in and out of the temporalis without biting down on something with the back molars (like the pencil). Now place the pencil between your front teeth (so it sticks straight out) and bite on it while feeling your temporalis. Does it bulge out less, or at all? The contraction is minimal when your back teeth are kept apart and not biting something! What if you could figure out a way to keep the pencil attached to your front teeth while you were asleep and dreaming and during stressful events during the day? Even though you would look ridiculous, your temporalis muscles would have time to relax, allowing their dysfunctional state to subside and headaches to resolve.

This is, essentially, the thought process that I went through. I had been wearing a TMJ (flat-plane) splint for five years, with no resolution of my headaches. I was making other people wear one, so I felt guilty if I didn't, too. At this point I realized that I was wasting my time and my patients' money on the traditional TMJ splint. My goal was to design an appliance that would significantly decrease muscle activity enough to rid me of my headaches.  Finally, in the summer of 1989, I designed what is now known as the Nociceptive Trigeminal Inhibition Tension Suppression System. The NTI-tss consists of two mouthpieces, one for day, and one for night.

The NTI-tss appliances keep the teeth discluded  ('disclude' means to separate, while the term 'occlude' means to meet or bring together) while sleeping and during stressful daytime events. Dentistry has been trying to influence muscle activity by controlling the occlusion (the bite). The occluding of the teeth, however, is already a dysfunctional act when not chewing. The NTI tension suppress system keeps the teeth from touching each other, which prevents temporalis muscle over activity and the resultant headaches! The first morning after wearing the NTI-tss appliance, I awoke with a strange sensation that something was definitely different.  Within a week, my headaches were dramatically diminished.  One month later, I was waking without headaches!


I soon realized that as I performed general dentistry all day long, I was constantly setting my teeth together.  Before using the NTI-tss at night, I never would have noticed.  Even though I had woke up without a headache (a result of using the NTI-tss at night), I usually developed one as the afternoon wore on. The simple act of setting one's teeth together throughout the day really doesn't cause anything.  But I still wasn't out of the woods. I still had a "pre-existing" condition…I was still clenching during my sleep, and even though the intensity was reduced (by the NTI-tss), the frequency and duration of the events remained the same.  Those years of off-the-map nighttime clenching intensity with the on going frequency and duration of activity still allowed even the seemingly harmless "teeth touching" during the day to trigger headache pain.  So the daytime NTI-tss was born. For the first four to six weeks of using the nighttime NTI-tss, the daytime is used to prevent those "harmless" jaw clenching events that irritate the fatigued temporalis and trigger a headache.  Once the nighttime jaw clenching intensity has been suppressed over several weeks, the typical chronic headache patient has less of a "pre-existing" condition to irritate, so the use of the daytime NTI-tss can be reduced or eliminated.

Although daytime teeth-touching/jaw-clenching can trigger a headache, it isn't as significant as the sympathetic nervous system's input to the spindle fibers.  Without my teeth touching, I could still sense the tightening and tensing of my scalp in response to stress (or whatever the "trigger" might have been).  As the weeks went by, those circumstances (triggers) which always seemed to bring on (worse) headaches just didn't have the effect that they used to.  Why?  Because the spindles were no longer residing within such dysfunctional musculature!

The first NTI-tss "anti-clenching" appliance I made was very bulky and awkward. I wore it only at night. I was single, so it didn't matter if I had a Frisbee in my mouth, as long as I didn't have a headache. What I had designed was anti-dentistry. All of my training had been focused on the extreme importance of  'the bite' and how it affected everything else. I was now suggesting not only that the bite was not so important, but also that biting was not normal to begin with (when not chewing). I kept this idea pretty much to myself, thinking that the 'dental god' might strike me down for such sacrilege.

Soon after, I began dating Kathleen (who is now my wife). Like the rest of us headache sufferers, she put on a pretty good act for a while. Little did I know that most of the time, just before our dates, she would take all the pain medications she could stand (not because I wasn't good looking or anything...). The first time I met one of her brothers, he asked her, quite casually, "Hey Kath, how's the headaches?"  "Oh, I'm doing fine...."  I could almost see it written on her face, "Shut up, you idiot, do you want him to know?!"  I don't think a girl wants a guy to know that she has a headache before they get married!  Later, after extensive questioning, I discovered her long history of migraines. While growing up, it was not unusual for her to miss a family function due to one of her headaches. It had become part of her, and her family practically expected it. She told me that the only thing which helped a little bit was a drug called Fiorinal. When I looked it up, I found that "Fiorinal is indicated for the relief of the symptom complex of tension (or muscle contraction) headache." Hey! Tension headache! I thought maybe I could help her. More than anyone else, I think my wife is responsible for the comfortable, current NTI-tss design. I had been satisfied with my original bulky (yet effective) version, but Kathleen wanted something comfortable to wear at night that would prevent her headaches, and at the same time, something she could wear in public during stressful daytime occasions without embarrassment. Eventually, with her encouragement, I came up with two designs that were just right: a daytime appliance that was hidden from view and didn't make speech difficult, and a nighttime appliance that was comfortable to wear and prevented her headaches...maybe that's why she married me.

"My husband had been out of work for six months because of his migraines. We had seen everyone who was supposed to be "the best" in the south, but with no luck. I read about Dr. Boyd and contacted him. Now, thanks to the NTI-tss system, my husband comes home from work smiling and plays with the kids...without a headache!"  Kim Reid, Selma, AL

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