Idiopathic condylar resorption (ICR) is a progressive alteration in condylar shape and a decrease in condylar mass and/or size for which there is no identifiable aetiology. The condition is usually bilateral and commonly occurs in females between the ages of 15 and 35 years. Patients can have temporomandibular joint (TMJ) symptoms, a Class II malocclusion with progressive anterior open bite due to clockwise rotation of mandible, retrognathism, and a decrease in posterior face height.

It is important to make the distinction between active and inactive ICR. This is done by history, serial clinical examination, evaluation of serial radiographs, and 99mTc labelled methylene diphosphonate (99mTc MDP) SPECT scan. If the SPECT scan is positive the disease is likely to be active.

Management of patients with idiopathic condylar resorption remains controversial. Orthognathic surgery has been advocated, but recurrence rates are high unless the resorptive process has ceased and there have been no documented occlusal changes and TMJ symptoms for a period of time before institution of treatment. Condylectomy and costochondral graft (CCG) reconstruction represents an alternative strategy for management of idiopathic condylar resorption. This treatment should be considered for stable patients requiring bimaxillary surgery and large mandibular advancements and all patients with active ICR.