Association between self-reported bruxism and anger and frustration.

Background Even though bruxism has been shown to be associated with several psychological factors, few studies have been performed on its relationships with anger and frustration. Objective This study aimed to determine the association between self-reported awake and sleep bruxism and anger and frustration. Methods In this longitudinal observational study, 55 healthy adult participants with "possible" bruxism reported their experienced level of bruxism and several psychosocial factors and lifestyle factors for 28 consecutive days using a personal logbook. The logbook consisted of a daily diary and a weekly questionnaire composed of Dutch versions of validated questionnaires. The primary outcome data were analysed using multiple regression models. Results An increase in SB of 1 unit (on a scale ranging from 1 to 10) was associated with an increase in the anger-scale of 0.03 units, and the frustration-scale of 0.04 units. However, the random intercepts were 0.22 for anger and 0.19 for frustration, meaning that there were major differences between individuals. For awake bruxism (AB), the effects were an increase of 0.04 for anger with a random intercept of 0.21 and an increase of 0.03 for frustration with a random intercept of 0.06. The effects of anger and frustration on both SB and AB were not statistically significant. Conclusion The association between anger and frustration and self-reported bruxism is small on group level. In individual cases, anger and frustration and self-reported bruxism may be co-existent.