Temporomandibular disorders (TMDs) are a significant public health problem, affecting approximately 31% of the adult population (Valesan et al., 2021). They are considered the most common cause of chronic pain of non-dental origin in the orofacial area (List and Jensen, 2017; National Institute of Dental and Craniofacial Research, 2018). TMD presents with characteristic clinical signs and symptoms, including temporomandibular joint (TMJ) and muscle pain, headache, joint noise (clicking), masticatory muscle tenderness, and irregular jaw movement (Thumati et al., 2014). TMD symptoms can be observed over a broad age range; a peak occurs between 20 and 40 years of age (Manfredini et al., 2011).

The primary method for diagnosing TMD is a clinical examination that is usually supported by radiographic imaging (Manfredini et al., 2007; Ohrbach and Dworkin, 2016). Clinical examination findings among patients with complaints suggesting TMD may not be sufficient and reliable alone to diagnose particular TMDs. MRI is a non-invasive, non-ionizing, and precise tool, widely used in diagnosing TMJ-related problems, and is regarded as the reference standard for diagnosing soft-tissue-related TMD (Manfredini et al., 2007).

MRI has been widely used to evaluate TMJ characteristics, such as disk morphology, disk position, and joint effusion. Although it is not considered the reference standard for TMJ bone evaluation, this imaging modality has also been used to evaluate osseous parts of the TMJ (Talmaceanu et al., 2018). Multiple studies have aimed to find the precise nature of the associations between MRI findings and clinical findings (Arayasantiparb et al., 2012; Roh et al., 2012; Koh et al., 2013; Dias et al., 2016; Vogl et al., 2016). Finding correlations between structural TMJ changes and clinical features may help to guide patient management and provide prognostic information. If the clinician knows which clinical symptoms should be supported by MRI when diagnosing TMD, it may be easier to dictate imaging protocols.

Relationships between the clinical signs and symptoms of TMD and MRI findings have been reported in the previous literature to some extent (Sano et al., 2000; Emshoff et al., 2002; Emshoff et al., 2003a,b; Kurita et al., 2004; Sano et al., 2004; Yajima et al., 2007; Larheim et al., 2001). For example, TMJ pain — the most common clinical symptom — has been correlated with various MRI findings, including internal derangement (Rudisch et al., 2001; Emshoff et al., 2002; Emshoff et al., 2003a,b), bone marrow abnormality (Larheim et al., 2001; Kurita et al., 2004; Sano et al., 2004), condylar degenerative change (Kurita et al., 2004; Yajima et al., 2007), joint effusion (Rudisch et al., 2001; Emshoff et al., 2003a,b), and bone marrow edema (Larheim et al., 2001). However, these correlations have not been confirmed in some other studies (Giozet et al., 2019; Pinto et al., 2021). In addition, the number of reports on the association between joint noise or deformity in jaw movements and MRI findings is limited (Matsubara et al., 2018).

Due to the high prevalence of TMD and its significance on the patient’s quality of life (Wurm et al., 2018), understanding the different clinical and radiographic associations of TMD is a critical step toward the timely diagnosis and optimal management of the disease by TMJ clinicians. TMJ treatment usually follows a staged approach, beginning with less-invasive conservative treatment and increasing the invasiveness as required. A definitive diagnosis of the status of the structural components of the temporomandibular joints is critical for treatment planning and incorporating more aggressive treatments, such as surgery, as needed. In addition, this information will provide radiologists with clinical signs/symptoms of TMD that patients may display when referred for advanced imaging. Threfore, evaluating the associations between TMD symptoms and MRI findings may show which symptoms warrant MRI examination; this will inform further diagnostic steps, including reducing unnecessary radiation exposure through other imaging modalities. This information will guide subsequent treatment and lead to better patient outcomes.

To the authors’ knowledge, this is the first systematic review aiming to comprehensively investigate the association between multiple clinical signs/symptoms (TMJ pain, masticatory muscle pain, clicking, limited mouth opening) and various MRI findings, including disk pattern, disk position, bone marrow signal pattern, and joint effusion in patients with TMD in the adult population.