Background: This paper systematically reviews the MEDLINE and SCOPUS literature to answer the following question: Is there
any evidence that bruxism may cause periodontal damage per se?
Methods: Clinical studies on humans, assessing the
potential relationship between bruxism and periodontal lesions (i.e., decreased attachment level, bone loss, tooth mobility/migration,
altered periodontal perception) were eligible. Methodologic shortcomings were identified by the adoption of the Critical Appraisal
Skills Program quality assessment, mainly concerning the internal validity of findings according to an unspecific bruxism
Results: The six included articles covered a high variability of topics, without multiple papers on the
same argument. Findings showed that the only effect of bruxism on periodontal structures was an increase in periodontal sensation,
whereas a relationship with periodontal lesions was absent. Based on the analysis of Hill criteria, the validity of causation
conclusions was limited, mainly owing to the absence of a longitudinal evaluation of the temporal relationship and dose-response
effects between bruxism and periodontal lesions.
Conclusions: Despite the scarce quantity and quality of the literature
that prevents sound conclusions on the causal link between bruxism and the periodontal problems assessed in this review, it
seems reasonable to suggest that bruxism cannot cause periodontal damage per se. It is also important to emphasize, however,
that because of methodologic problems, particularly regarding sleep bruxism assessment, more high-quality studies (e.g., randomized
controlled trials) are needed to further clarify this issue.