Relação entre os espaços articulares e os deslocamentos do disco da atm: avaliação por ressonância magnética

Abstract

This study aimed to evaluate the relationship between amplitude of joint spaces of the temporomandibular (TMJ) and different types of disc displacements, by means of MRI exams. Included in the study were MRI exams of 305 patients (610 joints) with ages ranging between 18-79 years (mean age 37.59 ± 13.85 years). Joint spaces were measured in paracoronal (medial space, MS; central space, CS, and lateral space, LS) and parasagittal (anterior space AS; superior space, SS, and posterior space, PS) planes. The collected data were tabulated and Chi-Square and Student t and Mann-Whitney tests were applied (p<0.05). Of joints, 348 (57%) presented articular disc displacements. Partial anterolateral displacement was the most common (27.9%) occurrence. Higher amplitude for MS and LS was associated with medial (p=0.004) and lateral (p=0.001) articular disc displacements, respectively. Lower amplitude for the CS was associated with posterior (p=0.001), anterior (p=0.003), rotational anteromedial (p=0.040) and anterolateral (p=0.002) displacements of the articular disc. Lower amplitude for the SS was associated with posterior (p=0.001), anterior (p=0.001), rotational anteromedial (p=0.001) and anterolateral (p=0.002) displacements of the articular disc. Lower amplitude for the PS was associated with anterior in addition to rotational anteromedial and anterolateral displacements (p=0.014) of articular discs. There was no association between higher amplitude PS and posterior displacement (p=0.234) of the articular disc. Our results revealed that disc displacements are significantly associated with changes in condylar position in the mandibular fossa, both in the parasagittal and paracoronal planes, and this information is essencial when evaluating images that do not show the articular disc.