Related Experiment Videos
Posterior disc displacement in the temporomandibular joint
P L Westesson1, T A Larheim, H Tanaka
1Department of Radiology, University of Rochester School of Medicine and Dentistry, NY, USA.
Purpose:
The purpose of this study was to describe the imaging characteristics of posterior disc displacement of the temporomandibular joint (TMJ).
Materials And Methods:
The study was based on 35 joints with posterior disc displacement and a control material of bilateral TMJ images of 62 healthy volunteers. The images were analyzed, and criteria for posterior disc displacement were developed.
Results:
Posterior disc displacement was characterized by the disc or a major part of the disc being located posterior to the superior prominence of the condyle. Three subcategories of posterior disc displacement could be identified: a thin flat disc, a grossly posteriorly displaced disc, and a perforated disc with a portion of the disc displaced posteriorly. Posterior disc displacement was not seen in any of the asymptomatic volunteers.
Conclusion:
Posterior disc displacement of the TMJ is rare but has probably been overlooked in the past because of a lack of well-defined imaging characteristics.