According to the Council of Dentists of Spain, Bruxism is the dental diagnosis that has increased the most since the pandemicalmost quadrupling: its incidence among the population has gone from 6 to 23%.
Whether we are affected or not, we all know what this behavior basically entails -clenching or grinding the teeth-, but in recent years the concept has changed and It is now classified into two distinct entities: sleep bruxism and wakefulness bruxism. And they can be approached as two independent phenomena, although sometimes they appear together.
While the first arises involuntarily while we sleep, the second manifests itself when we are awake. On this last case, the person may be aware of the behavior and therefore stop it.
two different phenomena
At the moment, Sleep bruxism is defined as “rhythmic or non-rhythmic masticatory muscle activity that is not a movement or sleep disorder in healthy individuals”. And that of wakefulness as “an activity of the masticatory muscles during wakefulness characterized by sustained or repetitive dental contact or by tension or thrust of the jaw”. Nor is it a movement disorder in healthy individuals.
In other words, what we popularly consider to be clenching/grinding our teeth when we sleep (whether at night or during the day) we would call sleep bruxism, while jaw tension, dental contact, or clenching when awake would be waking bruxism.
Although the two definitions seem to refer to very similar behaviors, their etiology, function and way of approaching them are different.
In some clinical settings, both modalities can be considered a risk factor or a sign of an underlying disease. For example, headaches (headaches and migraines) or temporomandibular disorders, which affect the jaw joint and the muscles that control its movement. And there is always the possibility that they will have negative consequences: they can cause tooth wear and fractures, as well as muscle or joint pain.
What if it was beneficial?
In any case, current research implies another important modification in the conception of bruxism: It is no longer considered a pathology, but a simple motor activity. That is, it does not have to be harmful in itself.
First, a 2020 study concluded that waking bruxism could be a stress escape mechanism. And secondly, the one that occurs while we sleep seems to be related to gastric reflux and obstructive sleep apnea (respiratory pauses during night rest). Some authors propose that it could play a protective role against the effects of both disorders.
The psychological factor
As for the etiology or origin of this behavior, it is still not entirely clear, but Risk factors such as alcohol, nicotine, recreational drugs, caffeine, some drugs, anxiety or stress have been identified. Emotional stress seems to play an important role, especially in waking bruxism. In fact, it is considered the main trigger.
In this line, a recent study carried out by researchers from the Faculty of Dentistry of the Complutense University of Madrid has compared samples of participants before, during and after the covid-19 pandemic. According to their conclusions, sleep and wakefulness bruxism could be influenced by different states of anxiety: while the first would be related to passive stress –associated with worry or helplessness–, waking stress seems to be linked to a greater extent to immediate daytime activity.
In a previous study, this same team found that bruxists who watched stressful negative videos with scenes of pain had greater muscle tension than non-bruxists. This relationship supports the linking of the most immediate and daily stress with the bruxism of wakefulness.
Therefore, and although vigilant bruxism may constitute an escape mechanism from stress, it can be prevented by learning to detect the habit – in order to reduce muscle tension – and then lowering stress levels through relaxation and coping techniques.
Perhaps for all this, one of the most effective treatments is the so-called ‘biofeedback’. Consists in that patients learn to identify and reduce muscle tension by adopting a mandibular resting posture thanks to the use of an electromyographdevice that measures the electrical activity of the muscles.
Many people are unaware that so that the jaw is relaxed and at rest there should be no dental contact, as can be deduced from the definition described above. The mere fact of being aware of it and trying to correct it reduces the incidence of bruxism.
Recently mobile applications have been developed to achieve these two objectives. However, they are usually not sufficiently optimized and are tedious.
Perhaps the easiest way to detect that we clench our teeth is to put a ‘post-it’ in visible places (computer screen, mirror, etc.) that remind us of it. And since stress is chronically present in our lives, habitually perform relaxation techniques and control that tensionthose that cost us less to do.
Laura Jimenez Ortega Professor of the Department of Psychobiology and Methodology in Behavioral Sciences, Complutense University of Madrid
Eva Willaert Jimenez-Pajarero Associate Professor of Prosthetics and Craniomandibular Dysfunction, University of Barcelona
Maria Garcia Gonzalez Professor of Dentistry, European University
This article has been provided by The Conversation
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