Temporomandibular Disorders in Patients with Rheumatoid Arthritis

Background and Objective: Rheumatoid arthritis (RA) is a systemic autoimmune disease affecting synovial joints including the temporomandibular joint (TMJ). This study aimed to assess the prevalence and characteristics of temporomandibular disorders (TMDs) in RA patients and correlate these findings with disease activity markers. Materials and Methods: This cross-sectional study included 40 RA patients meeting the 2010 ACR/EULAR criteria and 40 healthy subjects (HSs). Research diagnostic criteria for TMD were used to assess TMD. RA severity was evaluated using ESR, CRP, rheumatoid factor (RF), anti-CCP antibodies, Disease Activity Score (DAS) 28, and disease duration. Results: TMD prevalence was significantly higher in RA patients (75%) than in HS. Orofacial pain was a predominant TMD reported in 82.5% of RA patients. In RA patients there was a difference in myofascial pain, TMJ pain, and TMJ sounds in comparison to HS. All masticatory muscles were painful on palpation in RA patients and the pain intensity was higher in RA than in HS. The most painful muscles were the medial pterygoid muscles, the anterior belly of digastric muscle, and the tendon of the temporal muscle. Slight crepitations were the most frequent. Maximal active mouth opening was reduced and negatively correlated with CRP levels. The most frequent jaw function limitations were chewing and yawning difficulties and tinnitus. There were no correlations between TMD and DAS, RF, and disease duration. Conclusions: Active inflammation in RA is a crucial factor reducing mouth opening. TMD screening independent of disease duration should be integrated into RA management protocols, particularly for patients with elevated inflammatory markers, to eliminate other pathological factors contributing to faster TMJ functional changes, TMJ involvement, and the severity of TMD during RA course.