Study design: Systematic review.
Objective: To summarize the research on accuracy of individual clinical diagnostic signs and tests for the presence of temporomandibular disorder (TMD), and for the subclassifications affiliated with TMD.
Background: Diagnosis of TMD through clinical diagnostic measures has been reported in many studies; however, few of these studies have identified individual clinical tests or signs that can aid in the diagnosis of TMD or differentiate between the subclassifications of TMD.
Methods: Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed for this review. Computerized and hand searches were completed to locate articles on the diagnostic accuracy of clinical tests and signs. To be considered for review, the study required (1) an assessment of individual clinical measures of TMD, (2) a report of the diagnostic accuracy of these measures, and (3) an acceptable reference standard for comparison. Quality assessment of studies of diagnostic accuracy (QUADAS) scores were completed on each selected article. Sensitivity and specificity and negative and positive likelihood ratios were calculated for each diagnostic test described.
Results: The search strategy identified 131 potential articles, which were narrowed down to 7 that met the criteria for this review. After assessment using the QUADAS score, 3 of the 7 articles were of high quality. All 7 studies used tests to differentiate subclassifications of TMD. The 7 studies included (1) diagnostic tests/signs of joint sounds, (2) joint movements, or (3) clinically oriented pain measures. There were no studies that investigated TMD versus a competing, non-TMD condition.
Conclusion: Only 3 studies presented in this literature review were of high quality. Because all of the included studies assessed diagnostic accuracy among subclassifications of individuals suspected of having TMD, the ability of any of these tests to distinguish between patients with TMD versus patients without TMD remains unknown. Because of the lack of clear findings indicating compelling evidence for clinical diagnosis of TMD, and because of the low quality of most of these studies, the data are insufficient to support or reject these tests.
Level of evidence: Diagnosis, level 2a-.