Temporomandibular joint disorders in Sjoegren syndrome: A systematic reviewer

Aim: Sjoegren Syndrome (SS) is a chronic systemic autoimmune disease characterized by progressive lymphocytic infiltration of the exocrine glands and sicca syndrome. Oral functions impairment due to low salivary flow includes difficulty in chewing, swallowing, and talking, dysgeusia, tooth decay, mucosal atrophy. Muscular and nervous domains are frequently involved in SS but their clinical relevance in the orofacial district have rarely been investigated. The aim of this systematic review is to evaluate the possible association of temporomandibular joint disorders (TMJD) with SS. Methods: PubMed, Embase, Web of Science and Scopus databases were electronically searched for observational studies reporting TMJD or TMJ involvement in patients with a diagnosis of SS according to the 2002 American European Consensus Group (AECG) classification criteria. Only articles in English were included. Results: from 42 articles 7 relevant articles have been selected and read in full. SS patients presenting symptoms and signs of TMJ involvement ranged between 29% - 91% and prevalence of TMJD ranged between 29% and 54%. All con-trolled studies agreed on reporting a significant higher prevalence of TMJD in the SS group. Two studies reported a significant decrease in masticatory muscle activity 0and tongue strength compared to age-and-sex-matched controls. Conclusions: when investigated, symptoms and signs of TMJD are reported in most of SS patients, who show a much higher prevalence of TMJD compared to the general population (31% among adults, 11% in adolescents). More data are needed to assess the possible association between SS and TMJD and its causes.