Idiopathic condylar resorption in orthodontics

Abstract

Condylar resorption (CR) can be categorized into functional and dysfunctional remodelling of the temporomandibular joint (TMJ). The literature describes dysfunctional remodelling of the TMJ as idiopathic condylar resorption (ICR). Idiopathic condylar resorption (ICR) is a well-documented but poorly understood pathological entity that can occur spontaneously or post-orthognathic surgery. It predominantly affects young women, with other risk factors including Class 2 malocclusion with steep mandibular plane angles. It is distinguished by a decreased condylar head volume and ramus height, progressive mandibular retrusion and an anterior open bite. Its aetiology can be categorized into surgical and non-surgical risk factors. These include hormones, systemic disease, trauma, mechanical load and surgical risk factors, such as magnitude and direction of mandibular movement, type of surgical fixation and length of post-operative maxilla-mandibular fixation. ICR is a diagnosis of exclusion, and identified by a combination of clinical, radiographic and haematological findings. Multiple treatment options have been described in the literature, including medical management, orthodontics, orthognathic surgery, TMJ surgery, TMJ and orthognathic surgery combined, and total joint prosthesis reconstruction. Further research is required to better understand the aetiology of ICR and more long-term, controlled, multicentre clinical studies are needed to evaluate the outcomes of surgical and non-surgical management of CR patients. CPD/Clinical Relevance: Idiopathic condylar resorption has many presentations and potential causes that can greatly impact the decisions and outcomes for orthodontic/orthognathic treatment.