Association between axial spondyloarthritis and temporomandibular disorders: A systematic review

This study aimed to assess the frequency of temporomandibular disorders (TMDs) in patients with axial spondyloarthritis (axSpA) compared with the healthy individuals. We systematically searched PubMed, Embase, Scopus, Web of Science, CINAHL, and Google Scholar databases from their inception until 2022, without language restriction. A standardized dataset was used to extract data from the observational studies. Patients were required to have axial spondyloarthritis and clinical and/or radiographic evidence of temporomandibular joint dysfunction. Meta-analysis was performed with a random effects model. A systematic review was registered under number CRD42020206283. We identified seven relevant studies, which provided data for 745 patients and 216 temporomandibular disorders events. The combined odds ratio (OR) showed that the risk of temporomandibular disorders in individuals with axial spondyloarthritis was higher than the control group (pooled OR = 5.26, 95% CI 2.50-11, 06; p < 0.02; I²  = 58%). Also, these individuals do not appear to refer possible temporomandibular joint symptoms to the rheumatologist or dentist. The results of this systematic review and meta-analysis suggest that patients with axial spondyloarthritis have an increased frequency of temporomandibular disorders. TMDs seem to be secondary to postural alterations rather than direct involvement of the temporomandibular joints (TMJs).