Bruxism and oro-facial pain not related to temporomandibular disorder conditions: Comorbidities or risk factors?

Introduction: Bruxism has historically been of particular interest to the field of dentistry, primarily due to the inferred damage it may cause to the dentition and supporting periodontal structures. The definition of bruxism itself has undergone multiple changes over time. In addition, the effects of bruxism as it relates to oro-facial pain conditions has remained a debatable topic. Purpose: To review the available literature relating to bruxism and non-temporomandibular disorder (TMD) pain conditions. Methods: A literature search was conducted with the assistance of an expert librarian. The following databases were reviewed: PubMed, MEDLINE, EMBASE and Google Scholar. For additional references, articles were also retrieved by hand search from the selected papers. Any articles that were not published in English, or the focus were related to temporomandibular disorders were excluded. Conclusions: While bruxism and certain headache conditions do tend to occur together frequently, evidence relating to any clear common pathophysiological mechanism has yet to be fully elucidated. Robust evidence as it relates to the relationship between bruxism and other non-TMD oro-facial pains is also lacking.