This cross-sectional study will evaluate the association between sociodemographic, occupational, clinical conditions, psychological (sense of coherence), sleep quality variables and SB diagnosed by PSG, the gold standard exam with audio-visual resources obtained at Pelotas Sleep Institute.

Sleep bruxism is defined as a masticatory muscle activity during sleep that is characterised as rhythmic (phasic) or non-rhythmic (tonic) and should be considered a risk factor rather than a disorder in otherwise healthy individuals.

The diagnosis of sleep bruxism often is challenging and despite the use of questionnaires, clinical exams and portable devices, based on current knowledge, the polysomnography with audio-video recordings emerges as the gold-standard criteria for a definite sleep bruxism diagnosis.

Included on the questionnaire there is a registration form, which contains: included: age at time of data collection , gender, marital status , and education level ; Occupational: individuals were asked about work outside home, and working hours; Clinical condition: body mass index, smoking; alcohol consumption; use of sleeping pills; respiratory allergy and Psychological: sense of coherence .

Inclusion Criteria:

• All adults (aged 20 to 60 years) and elderly (aged >60 years)

Exclusion Criteria:

• Inadequate cognitive capacity to understand and answer the questionnaires;
• Degraded PSG image quality;
• Questionnaires filled incorrectly;
• Participants who presented a history of epilepsy that could interfere in the results of polysomnography.

All records obtained from adults (aged 20 to 60 years) and elderly (aged >60 years) who had undergone PSG at a private medical outpatients clinic from July 2017 to February 2018 were reviewed.