Evaluation of Temporomandibular Joint Structures and Conditions Using Dental-Dedicated MRI: A Feasibility Study

MRI is the most viable alternative to depict the soft tissues of the TMJ, and a recently developed dental-dedicated MRI (ddMRI) brings new possibilities to count on this technology at point-of-care.

To evaluate the feasibility of ddMRI for the assessment of temporomandibular joint (TMJ) conditions and to compare the evaluation of bony components with that of cone-beam computed tomography (CBCT).

CBCT and ddMRI images from 24 patients were independently assessed by three observers. Each TMJ side was evaluated for hard and soft tissue conditions (soft tissues assessed only with ddMRI), including flattening, cortical erosion, subcortical sclerosis, osteophyte, subcortical cyst, loose body, disc position, and joint fluid. Inter- and intra-examiner agreement and condition prevalence were calculated for each modality. Diagnoses of bone-related TMJ conditions were compared between imaging modalities using the McNemar test (α = 0.05).

The mean inter-observer agreement was 0.36 for ddMRI and 0.50 for CBCT; intra-observer agreement ranged from 0.444 to 1. The most prevalent finding was anterior disc displacement (58.3%). Bone conditions were more frequently identified on CBCT, with prevalence ranging from 2.1% (subcortical cyst) to 41.7% (flattening), compared to 0% and 31.3%, respectively, on ddMRI. In this feasibility study, no significant differences were found between CBCT and ddMRI for relevant hard tissue conditions (p > 0.05), supporting ddMRI's potential as an adjunct modality for TMJ assessment.

ddMRI is a feasible imaging modality for TMJ evaluation, enabling assessment of bony and soft tissue components, while avoiding ionizing radiation, which supports its potential clinical applicability.