Bruxism is repetitive jaw-muscle activity characterized by teeth clenching or teeth grinding. It can occur during sleep (sleep bruxism) or during wakefulness (awake bruxism). Sleep and awake bruxism may have different causes and different effects upon the jaw muscles and joints.
Frequently, the consequences of bruxism need to be managed in order to protect teeth and dental restorations. In addition, when bruxism is diagnosed by patient’s self-report, it is positively associated with myofascial (jaw muscle) pain (Manfredini, 2010). Bruxism is also associated with jaw joint dysfunction and noise (Jimenez-Silva, 2017).
Bruxism can be difficult to diagnose. Patients are not always aware of it. Tooth wear is not a reliable indicator of current bruxism, since it may be the result of past bruxism, functional wear, diet, and metabolic causes. Study in a sleep laboratory (polysomnography or electromyography) is the gold standard for diagnosis. Bruxism may also be diagnosed by direct observation, or by portable electromyography, an emerging technology with variable accuracy.
In 2013, an international consensus on defining and grading bruxism suggested classifying bruxism as (1) possible, based on patient’s self-report only; (2) probable, based on self-report and a clinical examination; and (3) definite, based on self-report, clinical examination, and polysomnography (Lobbezoo and others, 2013).
Sleep Bruxism Treatment Options
A recent systematic review of treatment methods for sleep bruxism found that there is not enough evidence to define a standard approach, with the exception of dental appliances (Manfredini and others, 2015). Therefore, in our practice, we treat sleep bruxism with acrylic mouth guards that fit over the upper teeth. A recent study found that intermittant use of a mouth guard (wearing it every other week) was more effective in reducing bruxism than continuous use (Matsumoto and others, 2015).
Extensive dental treatment, or any procedure that irreversibly changes a patient’s bite, are not proven methods for stopping bruxism. However, minor bite adjustments may be helpful in preventing the effects of bruxism. An example would be the adjustment of a tooth to take it out of the path of bruxism.