The term “bruxism” refers to all occlusal parafunctions occurring when awake or asleep that are accompanied by tonic (sustained) and/or phasic (rhythmic) jaw muscle activity. They manifest clinically by jaw clenching and/or tooth grinding (or rhythmic mandibular movements resembling chewing). In adults, the estimated prevalence of awake bruxism ranges from 22% to 30%, whereas that of sleep bruxism lies between 1% and 15% (Melo et al. 2019), making this dental parafunction a clinically significant phenomenon in the adult population.

In the dental literature, Károlyi (1901, 1902) was the first to report on these parafunctions; he referred to “spasmodic contractions of the masseter during sleep”. Five years later, Marie and Pietkiewicz (1907) introduced the term “bruxomania” into the French-language literature. “Bruxism” found its first mention in an essay by the American psychoanalyst Frohman (1931). In other words, the content of the term “bruxism” was always associated with occlusal contacts.

This regrettably changed in 2013, when an international consensus conference decided to include two additional but non-dental parafunctions, so the definition was expanded as follows: “Bruxism is a repetitive jaw-muscle activity characterized by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible” (Lobbezoo et al. 2013). Aside from the fact that one rarely sees patients in dental practice adopting the peculiar mandibular positions of bracing and thrusting, this is a prime example of how a term that has been precisely defined for generations is expanded without need (rather than creating a new term), causing confusion among parts of the dental community. In this article, therefore, the term bruxism will be used exclusively in its traditional sense, namely in the context of tooth contact during jaw clenching and/or teeth grinding.