Abstract
Introduction: Magnetic resonance imaging (MRI) is the gold standard for the diagnosis of internal temporomandibular joint (TMJ). However, it is frequently expensive, time-consuming, and not readily available. Furthermore, ultrasonography (US) has been suggested as a non-invasive, easy-to-access, and cost-effective alternative, but its accuracy as a diagnostic tool is debatable. Thus, this systematic review aimed to assess the current evidence regarding the use of US for diagnosing internal TMJ disorders compared to MRI.
Methods: PubMed, Web of Science, and Scopus international databases were searcherd for studies published from December 2000 to March 2022. A multiple search strategy involved the use of keywords, medical subject headings, and terms related to TMJ disorders (TMJ, internal derangement, and disc displacement), imaging modalities (ultrasound, Doppler, and MRI), and diagnostic accuracy using Boolean operators. Surveys comparing the accuracy of diagnosis between ultrasound and MRI were employed as a reference standard. No review articles, case reports, or studies were included in cases where data were inadequately provided to calculate diagnostic accuracy indices. The QUADAS-2 tool was utilizeds to evaluate the methodological quality and risk of bias of studies. References of relevant articles were also reviewed manually.
Results: The database searches identified 576 records. After removing 148 duplicates, 428 records remained for screening. Following tilte and abstract screening based on the eligibility criteria, 29 articles were assessed for full-text eligibility. Eventually, 19 articles were included and evaluated using the STARD checklist, which all achieved an acceptable score (at least 12 out of 27).
Conclusion: US may serve as an initial diagnostic modality for TMJ disorders. However, MRI remains warranted for confirmation in cases with abnormal disc position, surgical indications, or suspected medial disc displacement not excluded by US findings.