Temporomandibular disorders in immune-mediated rheumatic diseases of the adult: A systematic review

Objective: To systematically review the literature concerning temporomandibular disorders (TMDs) in immune- mediated rheumatic diseases (IMRDs) of the adult. The temporomandibular joint (TMJ) outcomes used in clinical studies, the prevalence of TMDs in IMRDs and the risk factors for their development were qualitatively synthetized. Methods: A literature search on PubMed Central, Embase and Cochrane Library databases was performed for studies including TMJ outcomes in IMRDs patients compared with healthy controls, other rheumatic diseases or in the assessed IMRDs patients after follow-up and treatment. Among the IMRDs of the adult, original articles investigating TMJ involvement in inflammatory polyarthritides and/or autoimmune connective tissue diseases were considered. The quality of the studies was scored using the Newcastle-Ottawa scale (NOS). Results: Of the 3259 screened abstracts, 56 papers were included in the systematic review. Most of the papers (77%) investigated TMDs in rheumatoid arthritis (RA) with a prevalence of signs and symptoms varying from 8% to 70%. The risk factors for TMDs development in RA were female sex, younger age, anti-citrulline peptide autoantibodies (ACPA) positivity, higher disease activity, cervical spine involvement, cardiovascular and neuropsychiatric comorbidities. Ten papers (18%) evaluated TMDs in spondylarthritides (SpA) reporting a prevalence of symptoms and signs in 12%-80% of patients with higher TMDs prevalence in patients with radiographic spine involvement, skin psoriasis and HLADRB1×01 positivity. Among autoimmune connective tissue diseases (CTDs), systemic sclerosis (SSc) displayed the highest evidence of TMDs patient-reported out- comes (PROs) and clinical findings (20–93%), followed by systemic lupus erythematosus (SLE) in 18–85%, primary Sjogren’s syndrome (24–54%) and idiopathic inflammatory myopathies (4–26%). In SSc and SLE, TMDs were more frequent in patients with higher disease activity and duration, correlating with the extent of skin fibrosis in SSc and with renal involvement in SLE. Conclusion: TMDs in IMRDs display a significant relevance in the rheumatological clinical practice even if often misdiagnosed. This burden is epidemiologically important in terms of PROs and clinical findings which correlate with disease activity in RA, SpA, SSc and SLE. The early recognition and multidisciplinary management of TMDs is warranted and should be aimed at hindering the TMJ structural damage maximizing the quality of life of patients.