Idiopathic condylar resorptions: 3-dimensional condylar bony deformation, signs and symptoms

•Idiopathic condylar resorption (ICR) changes the size and shape of the condyle.•The localization is unspecified, and often the entire condyle is affected.•Most patients will have nonspecific symptoms or signs of TMD, but some are asymptomatic.•Epidemiologic and radiographic parameters to diagnose ICR are presented.•Distinct clinical diagnostic criteria for ICR were not found.

IntroductionOur aim was to describe 3-dimensional condylar deformation of the temporomandibular joint (TMJ) and symptoms and signs of temporomandibular dysfunction (TMD) in patients with idiopathic condylar resorption (ICR).MethodsWe included 25 patients with ICR and 25 controls. We performed cone-beam computed tomographic scans and analyzed condylar width, length, and height as well as the condylar axial angle and the condylar neck angle. TMJ cross sections were evaluated for degenerative characteristics and location of bony deformations. Furthermore, symptoms and signs of TMD were described in the ICR group.ResultsIn the ICR group, we found statistically significantly reduced condylar width (mean difference, 2.0 mm), height (mean difference, 4.9 mm), and condylar axial angle (mean difference, 10.6°); 84% of the TMJs had a posterior condylar neck angle (control group, 22%). The most common degenerative changes were noncongruent shape of the condyle-fossa relationship (72%), condylar resorption (56%), and nonintact cortex (40%). More than 70% of the joints with bony deformations showed changes along the entire condylar head. Most patients with ICR showed symptoms and signs of TMD; nevertheless, 12% had no signs or symptoms of TMD.ConclusionsICR in the TMJ changes the shape and reduces the size of the condyle. Deformity locations are unspecified, and the entire condyle is often affected. Most patients with ICR have signs or symptoms of TMD; however, a small group was asymptomatic and without clinical signs.