Understanding the Internal Derangement and Degenerative Joint Disease Process Through Radiographic Imaging

The most common intracapsular TMJ disorders encountered by the clinician are the sequelae of biomechanical failure of the articular tissues. They are often thought of as a continuum, with the gradual failure of the soft tissues (internal derangement) followed by the gradual failure of the hard tissues (DJD), although some cases of advanced hard tissue degeneration and change can occur with macrotrauma without passing through some of the initial long term gradual soft tissue changes. This article aims to help the radiologist understand the process of biomechanical breakdown and the changes along this continuum as they appear radiographically on MR imaging and CT/CBCT to aid in the correct identification and diagnosis of this condition, and to give the referring dentist the clinically relevant information they need.