Clinical criteria for the diagnosis of awake bruxism. A Preliminary study.

Bruxism is defined as a repetitive jaw-muscle activity characterized by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible. Bruxism has two distinct circadian manifestations: it can occur during sleep (indicated as sleep bruxism) or during wakefulness (indicated as awake bruxism). At present, there are validated diagnostic criteria available for sleep bruxism only. There are no clinical features for the diagnoses of awake Bruxism. Therefore, the aim of the present study was to identify clinical findings that contribute to detecting each of the entities, and to develop diagnostic criteria for awake bruxism. METHODS: A self-reported questionnaire was administered to 100 patients diagnosed with bruxism, in order to group them as sleep bruxism, awake bruxism or mixed bruxism. In the case of patients with awake bruxism (n = 6), clinical records were filled in, and study models and photographs were taken. The presence of vestibular bone exostosis, palatine and mandibular torus was recorded. We attempted to determine the presence and type of tooth wear in order to identify a pattern of mandibular movement. Ninety-five percent (95%) confidence intervals were calculated for percentages (CI95) using the Wilson score method. RESULTS: The study comprised 6 patients, age range of age 24 to 64 years, and a median age of 34; 83% (5/6) were men and 17% (1/6) were women. Five subjects (83%, CI95: 44% to 97%) had vestibular bone exostoses in the molar and premolar region of the maxilla. All six patients (100%; 95% CI: 61% to 100%) presented an over-contouring of the anteroinferior alveolar ridge (anterior bone balcony). The presence of mandibular torus was observed in four patients (67%, 95% CI 90% to 90%). None of patients had a palatal torus. In five patients (83%, CI95: 44% to 97%), tooth wear compatible with centric movements was observed, and only 1 showed wear facets compatible with eccentric movements of the jaw. Conclusions: The present findings suggest that awake bruxism presents different clinical characteristics as compared to sleep bruxism. The type of tooth wear and the presence of exostosis could be distinguishing features to be taken into account for proper diagnosis.