The rude awakening comes to the dentist. "But there's a lot of crunching," she says during my check-up appointment, sounding reproachful. Teeth grinding – me? I can't imagine that. Why don't I know about it? Very simple, as my dentist explains to me: because I sleep like many others. According to a systematic literature review, around 13 percent of adults work vigorously with their jaws at night. Up to 31 percent do this even during the day without eating anything.
Based on the abrasion marks on the teeth, the doctor reconstructs how I move my jaws at night. The movement she is guiding me to feels amazingly familiar. So that I do not continue to grind off the teeth, I get a splint for the lower jaw. So from now on I'm supposed to sleep with plastic in my mouth. Not a nice performance. To cheer me up, the dentist tells me that some people even wear splints voluntarily. Among other things, this could increase performance in sports. As an ambitious amateur athlete, I am getting clairaudient. How is this supposed to work? Is there a previously unknown connection between teeth, brain and muscles? Can the power of the jaw be used positively in the end? After all, when grinding teeth, ten times the normal chewing force can act.
The research results: it is complicated again. You have to distinguish at least three types of tooth rails. First of all: The copy that I got - transparent, relatively soft and flexible - will certainly not make me more powerful, even if I would wear it during sports. The rail will probably not prevent me from grinding my teeth. Then what is the thing for? "The classic crunching rail is basically just wear protection," says Rainer Hahn, head of a dental care center in Tübingen. You give the teeth a soft cover so that they remain salvation despite the nocturnal jaw activity.
By the way, experts do not speak of teeth grinding, but of bruxism. This includes not only the sliding over and together of the teeth, i.e. the classic grinding; this also means a convulsive compression of the jaws. And then there are the smacks or hackers. "They work in rhythmic movements with their teeth," reports dentist Ingrid Peroz from the Berlin Charité. Bruxism also includes tensing the jaw muscles without the teeth coming into contact at all.
Some people grind, press or chop their teeth during the day without realizing it. Others press the tongue against the teeth or pull the cheek inward and chew around on it. "In some patients, the mucous membrane is already completely white," says Peroz. A horny layer is formed. "By definition, bruxism is actually just an activity of the masticatory muscles," the senior physician continues. Together with colleagues, she has written the current guideline on the topic. According to this, bruxism should not be considered a disease at first – unless it leads to extreme wear of the teeth or is associated with diseases, for example, sleep apnea.
Some people claim their jaw muscles so strongly that they can hardly open their mouths. The whole head hurts them or the temporomandibular joint cracks. "That can be very painful," says dentist Hahn. In such cases, one speaks of a "craniomandibular dysfunction". Bruxism is considered a risk factor, but not every cruncher develops such a clinical picture. It has about 10 percent of the general population; Up to 80 percent of those affected are female. With bruxism, this is not the case to grind men and women alike.
Using teeth grinding as a stress-reduction method
The causes of bruxism, the guideline states, are "multifactorial and partly unknown". While in the past it was assumed that it was related to the position of the teeth, today people tend to focus on stress, anxiety and sleep disorders. Likewise, genetic factors, a lack of certain neurotransmitters, as well as nicotine, alcohol or drug use may also play a role. Even though health insurance companies are prescribing more and more grinding splints, grinding teeth is not a modern problem, says expert Peroz. Already in the Neanderthals one would find worn teeth, which indicated a strong activity of the masticatory muscles. To what extent they also crunched, although one could not say. But the fact that emotions have an influence on the chewing muscles is certainly laid down in evolution.
»This evolutionary pattern is in each of us, also in animals. We have had that for millions of years, «her Tübingen colleague Hahn agrees. Feelings such as anger or aggression often trigger a strong jaw tension, the lower jaw is pushed forward in corner tooth position. This is responsible for this, a nerve network called formatio reticularis that pulls through the brain stem to the spinal cord. It regulates emotions, motor skills and other vital functions. These nerves are closely connected to the jaw muscles.
Researchers have found that aggressive biting lowers, among other things, the level of the stress hormone norepinephrine. Gritting your teeth could therefore help to cope with stress. Because the signal comes from the brain, it's hard to fight it. "There is no causal therapy with crunching splints," says Hahn.
But this does not mean that you can not have any influence on the jaw muscles with dental splints. There are highly sensitive sensors in the root skin of the teeth: the Ruffini corpuscles register every fiber, every tiny grain between our teeth and report it to the brain. This in turn sends a signal to the muscles. Hahn has an example ready for this: "Imagine that you bite on a cherry kernel. Her jaw immediately lets go." So the Ruffini bodies will very well notice that I have a crunching splint in my mouth. As a result, the brain signals to the jaw muscles: "You need to work differently." After all, the distance between the pines is suddenly less. "This can lead to a relaxation in the first moment," says Peroz. However, if a patient has got used to the splint, he usually continues to crunch as before. After all, the teeth are protected in the process.
In cases of hardship, therapy rails
A second type of dental splint acts specifically on the receptors of the periodontium. At first glance, such therapy splints are not so easy to distinguish from ordinary crunching splints, says Oliver Ahlers. The specialist for functional diagnostics and therapy operates a practice in Hamburg-Eppendorf. Opposite is the University Hospital, where he teaches and researches as a private lecturer. In most cases, therapy splints are also transparent, but they are made of other materials and are manufactured differently. And, most importantly: "They are based on dedicated diagnostics," explains Ahlers. While simple impressions are sufficient for a crunching splint, special examinations are necessary for the preparation of a therapy splint.
The result: "A complex, neuromuscular reflex pattern tool," says Hahn, who also adapts such rails. "Depending on how I form this, I can address the Ruffini bodies in the opposite jaw in different ways," explains the dentist. You could make the biscuit points more hard or soft. If you stimulate all the receptors at the same time, the muscles relax, the symptoms let up. Because you wear out over time, a dentist has to measure and rework the points regularly.
In addition, wearing the splint can change the position of the jaws and thus the bite. This may interfere with the interaction of teeth and existing crowns, bridges or implants; teeth and dentures may have to be ground down or remade. Sometimes an orthodontist needs to intervene. Because new treatments may be necessary, a therapy splint is never made lightly, but only if someone has severe and persistent complaints, says Hahn.
Treatments for clenching and grinding
No generally effective healing method is currently known. There are only a number of approaches that lead to success in some cases. However, they were mostly only tested on a small group and over relatively short periods of time. These include:
• Relaxation techniques such as progressive muscle relaxation or autogenic training • Cognitive behavioral therapy • Biofeedback (the tension of the jaw muscles is measured and reported back via a sound) • Injections of Botox into the jaw muscles (off-label use, not recommended in the guideline)
Source: Guideline on bruxism
The situation is different with sports tooth rails. They are intended to improve the performance of healthy athletes. More strength, mobility, endurance and improved coordination-that and even more promises manufacturers of so-called "performance tooth rails". Mind you, these offer no protection against tooth damage due to punches, for example when boxing, for which additional protection is required. The also transparent, hard sports rails are practically a further development of the therapy rails, says Hahn. He works with a company that produces functional tooth rails, among other things. The dentist explains signals in turn via the Luffini bodies. Instead of relaxing the muscles, however, one now wants to achieve that certain movement patterns are called up faster. These are also stored in the stem brain, says Hahn. The result: "The movement becomes more symmetrical and you can use your strength more effectively."
Why do toothed splints give me more strength?
According to Hahn, the most noticeable effects can be achieved in sports where a lot of coordination is required. According to a study from South Korea, professional golfers hit faster, further and more precisely with a splint. Strength athletes, runners, sport shooters or ball athletes also showed better performances with splints in their mouths. Overall, the study situation is ambiguous, the samples are usually manageable. For example, researchers at the University of Frankfurt let 20 young recreational runners pass by – once with, once without a splint. With the help of special cameras, they analyzed their movement patterns and came to the conclusion: with rail, things are more symmetrical. This can help to reduce the risk of injury or improve performance.
An investigation from Portugal, on the other hand, could not find any significant differences. This is not surprising to the specialized dentist Ahlers: "If you look for studies on one and the same question, you will find diametrically opposite results." Although this also occurs in other research areas, it is particularly noticeable here. An Italian study indicates that people can react very differently to the rails; Therefore, individual examinations are required.
One reason for this is that running is a complex sequence of movements. Numerous factors can influence this. "With new shoes, for example, you walk differently," says Peroz. Everyone has personal asymmetries or weaknesses. And the further you physically move away from the temporomandibular joint, the more potential disruptive factors are added. The dentist doubts whether the study results are always related to wearing a dental splint.
Spinal issues can result from chewing issues.
It has been proven, on the other hand, that problems with the chewing organ can affect the cervical spine and the entire body statics. Ahlers knows the reason: "Our body is a combination of function chains." That means: Similar to the limbs of a chain - the muscles of our entire body are connected. The upper end of the front function chain represents the chewing muscles. As long as the mouth is open, it is interrupted. However, if you bit your teeth together, it closes. "You can feel muscle strands on the neck that continues to the collarbone," says the expert. Additional power can be mobilized via this chain closing, which helps, for example, to lift loads. According to Ahlers, this is exactly what the effect of such tooth rails is based on.
That makes sense. It is not for nothing that we grit our teeth – literally and intuitively – when we are faced with a difficult or strenuous task. But how does this fit in with the mechanism postulated by his colleague Hahn? "Maybe we're both right. It is quite conceivable that two mechanisms are at work here," says Ahlers. Unravelling them is complicated. For example, one would have to measure the metabolic activity of the test persons in certain brain regions while they are doing sports – sometimes with, sometimes without a dental splint. Such studies do not yet exist.
So should I get a second rail that I bite about during sports? According to Hahn's estimate, there are already 1500 to 2000 -certified sports toothed doctors over Germany who can adapt such sports tooth rails. It is a significant part of it himself in Tübingen. There is also a corresponding curriculum in Nuremberg. At least 200 to 300 euros you have to spend on a sports tooth rail, says Hahn.
Is the athlete track harmful?
Some professional athletes swear by it. The downhill mountain biker Simon Maurer, for example, says that his track gives him a performance boost, he can really get a lot out of it. "Really a lot" in his case means: eight seconds. "Recreational athletes will usually not notice anything about this," says Ahlers. This could explain the heterogeneity of the study results. Perhaps the subjects were not all trained enough. So far, it is unclear what exact requirements a person must meet in order for a splint to increase their athletic performance.
On the other hand, it is certain: the tools are not suitable for everyone. Because you only wear it to sport, there is no risk of changing the bite. This requires a daily wearing time of at least eight to twelve hours, says Hahn. But: "The tooth rail makes it possible for sports, strengthen your teeth and load the chewing organ," says Ahlers. It is not proven, but it is possible that this promotes bruxism. If you already have problems with the temporomandibular joint, you should first be treated. In order to spread such knowledge among dentists, Ahlers recently published a corresponding division together with his colleague Holger Claas.
Since I am not a professional, but a cruncher, I do without a sports dental splint. Instead, I dutifully wear my crunching splint and try to avoid stress. By the way, the chances are good that the teeth grinding stops all by itself: In the second and third decade of life it is most common, after which apparently many jaws relax again.
