"What is the success rate?"
That depends on what the presentation of the patient. Dentist who are using the NTI-tss exclusively for TMD patients are getting very, very good results. Based on the reports I've been receiving, even those patients who seem to not respond to any TMD treatment do quite well with the NTI-tss (testimonials). Migraine patients are different. Unlike the protocol for the TMD patient, the dentist can not miss a trick when providing an NTI-tss to a migraineur. While at the Headache Prevention Institute, 75% of migraineurs had a significant or their frequency and/or intensity of their migraine episodes. In the trials that are underway right now, comparing the NTI-tss to a control device, will have more reliable numbers and is expected to be published in the summer of 2000.
"What do teeth have to do with headaches and migraine pain?"
Actually, teeth have nothing to do with headaches and migraine pain. Let's not forget the simple definition of migraine: a debilitating headache accompanied by nausea and/or sensitivity to light and/or sound. It doesn't matter what kind of teeth you have, or where your teeth are located, but it does matter what you do with the muscles that control your teeth (like clench).
Medical science has not yet figured out how to prevent common migraines, just how to medicate the attack. I don't believe the medical community understands how intensely headache/migraine sufferers use their temporalis muscles! Maybe it took someone who had tension headaches and common migraines, and had a background in muscle physiology and jaw dynamics, to figure it out.
Here's an example. I was visiting a clinical psychologist who specialized in biofeedback for patients who have tension headaches and common migraines. I was curious to know what my maximum clenching reading would be on his EMG (electro-myo-graph) machine. These machines are used to tell how tense a muscle is; that is, how much a muscle is contracting. My request was somewhat strange because bio-feedback is supposed to teach you to achieve the most relaxed state. After gluing the electrode pads to my temporalis muscle, I clenched as hard as I could, and the reading went off the scale. The doctor recalibrated his machine. I clenched as hard as I could, and again, off the scale. This happened once more before he could calibrate the machine to accurately measure my clenching intensity. I asked the therapist if he suffered from chronic headaches and migraines. He didn't. Just for fun, I suggested we wire him up to see what his temporalis muscles were capable of. We left the machine at my last calibration setting for his first trial at maximum clenching. He couldn't get a reading! We recalibrated the machine to its original setting. This time we were able to record his maximal reading. We discovered that my temporalis muscles were three times more powerful than his. I was the Arnold Schwarzenegger of clenching! Here was a headache specialist who had no idea of what a headache patient's temporalis was capable of!
Here's another example. A research group set out to see if normal clenching could cause common migraines. Migraine patients were instructed to clench their teeth at one third of their maximum ability for thirty minutes. The researchers assumed that this should be more than adequate to cause a migraine (if it were possible) because previous studies had shown that clenching activity was less than one third of maximum during migraines. Therefore, they figured that one third of maximum would be more than enough to cause a migraine. I've been suggesting that clenching occurs well before the migraine and is far more intense than one third of maximum. The researchers advised the subjects that they would be allowed to take a break every ten minutes for a rest. To the researchers' surprise, most of the subjects breezed through the experiment, without stopping to rest, and no one got a migraine. What the researchers hadn't realized was that the subjects had been in 'training' for years! Thesewere the All-Stars of clenching, and one third of maximum didn't even tire them. What the researchers did prove then, was that migraines can be prevented by limiting the intensity clenching!
"Can the NTI-tss appliance stabilize the jaw joint and is it good for TMD patients?"
Mouthpieces for TMD patients are supposed to do three things: protect teeth from grinding, decrease strain and pressure in the joint during clenching and grinding, and reduce muscle parafunction. The NTI-tss prevents teeth grinding by providing an air space between the teeth. Second, jaw joint strain occurs only when clenching or grinding occurs on the side opposite the joint. The NTI-tss design provides for the least amount of joint strain possible by not allowing clenching or grinding on either side. Finally, the NTI-tss design decreases maximum temporalis muscle activity by 66 to 82 percent while the traditional TMD splint can actually increase muscle activity in some patients; thus a NTI-tss appliance is an ideal splint for TMD patients.
"Do the teeth move?" (Can the back teeth "supraerupt")
No. The way dentists and orthodontists move teeth is by applying a slow, constant pressure to the teeth, and the teeth then move away from the pressure source. The protective jaw muscle relaxing reflexes that the NTI-tss activates prevents the amount of force necessary to move the lower front teeth when they contact the appliance.
Back molars, to maintain their positions, require regular chewing stimulation. For example, if a lower molar has been extracted, there is nothing for the upper molar to contact against during chewing, thus eliminating its normal regular stimulation. The upper molar, over several months, slowly drops down a little, or 'supra-erupts', looking for the lower opposing molar (which is gone) to chew against. Some dentists might quickly assume that supra-eruption of the back molars is possible with the NTI-tss. However, since it is impossible to use the NTI-tss while eating, the back teeth receive daily stimulation during normal chewing, so they never have a chance to supra-erupt (I've worn mine nightly for 11 years, and no supraerption yet).
However, there are situations where it seems as though teeth have moved following months of NTI-tss use. A small percentage of patients have report that as their headaches begin to taper off, they notice that their teeth don't meet the same way they used to. Their 'bite' has changed, and they naturally assume that their teeth must have moved. Here's what really happens. First, it is important to understand that the jaw bone is like a big, flexible horse-shoe that is merely suspended from your skull by a 'sling' of muscles. Similar to a garage door whose springs swing and pull the door closed, the jaw muscles swing and pull the jaw closed. These muscles are particularly powerful, and when they are in a dysfunctional state they are capable of 'bending' your jaw-bone ever so slightly, and are capable of holding the jaw bone within it's joint space in an unnatural position (which complicates headaches and TMD). In this condition, the patient develops a familiar "bite". Once the muscles are allowed to relax and become comfortable, the jaw-bone 'unbends', and/or the way the jaw-bone is suspended from your skull changes slightly, allowing the jaw to seat better into the joint space. The lower jaw actually assumes its natural and optimal shape and orientation, and its arc of closure changes. Just as the fit of the closed garage door changes when the tension of the springs changes, so does the fit of the teeth change when the
tension of the muscles changes. The arc of closure is the path on which the muscles take the jaw during closure. Since the muscle tension is different, the path is different, and therefore, so is the final point of closure. Patients then notice changes in the way their teeth fit together. It is important to remember that for the musculature and joint, this is an improvement over the original condition and is a desired effect. In traditional TMD therapy and in NTI-tss therapy, once the patient's TMD symptoms or headaches are gone, the dentist and/or the patient may want to modify the teeth so they fit to the patient's comfort.
"Why is it that I can feel a headache coming on and I'm certain that my teeth aren't touching?"
Remember pushing on your temporalis muscle and finding some spots that were more painful than others? Those painful spots are called trigger points. Here's how they are created: Within every muscle there are specialized muscle cell bundles called spindle fibers which extend the full length of the muscle. Spindle fibers are like individual rubber bands which your sympathetic nervous system has special control over. The sympathetic nervous system controls the reactions to fear and threat, like hair standing on end, pupils dilating, muscles tightening, cold sweat, etc. The sympathetic nervous system adjusts the tension of the spindle fibers that sets the overall 'tone' of the muscle. When the spindle fibers are tightened, the overall length of the muscle is shortened. When the spindle fibers are relaxed, the muscle is more easily stretched and lengthened.
In some patients, the sympathetic nervous system works overtime and maintains several of the spindle fibers of the temporalis in a contracted state (reference). Over a period of time, these fibers themselves become painful, and are called trigger points. When a stressful event occurs, the sympathetic nervous system over-reacts and begins to tighten the already fatigued and sore spindle fibers of the temporalis (or another muscle, like the lateral pterygoid, trapezius, or sphenomandibularis). The patient becomes aware of a general tightness over the scalp, followed by a headache. Ex-migraine patients who are now headache-free after wearing the NTI-tss often wonder why their injectable drug, Imitrex, stopped their migraines. One possibility is that the Imitrex interrupts the sympathetically controlled spasming of the spindle fibers.
This is where the daytime version of the NTI-tss comes in handy. Even though the back teeth aren't clenched, the lower front teeth will still tap on the appliance and activate the jaw opening reflex. This causes the musculature to relax and counteracts the tightening of the spindle fibers!
By the way, it is also the presence of trigger points within the lateral pterygoid muscles (the muscles responsible for moving your jaw from side to side) that chronically bends the jaw bone. When the trigger points resolve, and the spindle fibers relax, the jaw bone 'unbends'. In addition, it is the trigger points within the lateral pterygoid muscle which present with 'sinus' pain.
"My mother had taken me to every specialist in Oklahoma...but when we booked a flight to see Dr. Boyd, I knew she was desperate (she'd never been on a plane before)! We arrived on a Friday afternoon and left Sunday morning...without a headache! Words cannot express my gratitude." Anita Clark, Tulsa, OK
"Dr. Boyd's analysis of the causes of persistent headaches is the most logical and complete formulation I have seen. The use of the NTI-tss to break the cycle of muscle spasm and subsequent pain is a simple, safe and effective way to alleviate often intractable headaches. While there are certainly other factors operative in the causation of headaches, the use of the appliance would appear to be an excellent first choice in their treatment. Other approaches such as drugs, manipulation and acupuncture are time consuming, expensive and/or may have significant side effects, while not addressing the basic problem. Use of the NTI-tss appliance with adjunctive therapy of other modalities as needed would seem to be the ideal way to approach patients with chronic headaches." Carl Muchnick, M.D., Los Angeles, CA
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