Objectives: To assess the association between depression in individuals with different bruxism classification (i.e., unspecified, sleep and/or awake bruxism). In addition, to assess this association among different depression and bruxism assessment methods, bruxism types, and the changes of this association between 2002 and 2025. Materials and Methods: A systematic review search following the PRISMA guidelines was performed in
PubMed/MEDLINE, Embase, Brazilian Dentistry Oral Sciences. Observational (i.e., cross-sectional, case-control, and cohort) studies published since 2002, with young adult population (18-59 years old), and with no restriction regarding diagnostic method for both depression and bruxism were included. Articles selected for systematic review and meta-analysis underwent quality and heterogeneity evaluation. Results: Forty-eight articles were included in the systematic review, and 26 in the meta-analysis. Depression levels were found to be higher using standardized mean differences in all types of bruxism assessed in the literature (i.e., unspecified bruxism, sleep and/or awake bruxism), regardless of the diagnostic method used for bruxism or depression, with the exception of electromyography for the diagnosis of sleep bruxism, which was non-significant. The positive association found in most studies remained positive overtime (2002-2025), without significant changes. Subjects with bruxism in general (i.e., unspecified, sleep and/or awake) had 2.84 times the odds of having depression than those without bruxism. Conclusions: Assessment of depression and other psychological conditions should be considered in the multidisciplinary management of both sleep and awake bruxism. Both sleep and awake bruxism must be reported and assessed, separately and in combination, in all association studies with depression.
