Prevalence of psychosocial impairment in temporomandibular disorder patients: A systematic review

Background: Several studies have described high levels of psychosocial disorders in patients with temporomandibular disorders (TMD), but an estimate of their prevalence in populations of TMD patients has never been assessed systematically. Objective: To conduct a systematic review of the literature on the prevalence of research diagnostic criteria for TMD (RDC/TMD) Axis II findings in TMD patients. Methods: Search for articles was carried out by two independent researchers to retrieve papers published after 1992. Inclusion was reserved to observational studies with a minimum sample size of 100 individuals, which used RDC/TMD diagnostic protocol. Quality assessment was performed with the adoption of the methodological evaluation of observational research (MORE). Results: A total of 1186 citations were obtained from search strategy, but only 14 filled the inclusion criteria. Included papers reported somatisation, depression and/or pain-related disability prevalence or scores from populations of 12 different countries. A broad range in the prevalence of moderate-to-severe somatisation in patients with TMD was observed, ranging from 28.5% to 76.6%. Similar results were found for depression, with moderate-to-severe levels in 21.4%-60.1% of patients. Finally, most patients were rated as grade I or II of the Graded Chronic Pain Scale, whereas high pain-related impairment was present in 2.6% to 24% of the individuals. Conclusion: The prevalence of severe-to-moderate somatisation and depression was high in TMD patients, while severe physical impairment was not commonly reported.