Chronic mandibular hypomobility related to a unilateral accessory condyle. A case report

Chronic mandibular hypomobility is characterized by a long-standing limitation of the mouth opening related to multiple etiologies, including elongation of the coronoid apophysis. Unlike the most frequent pathologies that cause coronoid elongation, such as hyperplasia, osteoma (OM), and osteochondroma (OC), the accessory mandibular condyle (AMC) is a rare entity. Clinical Presentation: The AMC shows a configuration similar to a normal mandibular condyle with an articular surface covered by fibrocartilage that articulates with the temporal wall of the zygomatic bone, and histologically, does not show neoplastic growth. The patient was treated with a coronoidectomy, removing the coronoid apophysis as well as the AMC.

This case report presents a case of an AMC to describe the clinical, imaging, surgical, and histological characteristics, establishing its differential diagnosis with hyperplasia, OM, and OC of the coronoid apophysis.