Limitation of mouth opening caused by osteochondroma of the coronoid process.

Background: Osteochondroma at the level of the coronoid process is unusual, causing a slowly progressive facial asymmetry and limitation of mouth opening. Histologically, it is a bone tumor covered by a thin capsule of cartilage. We present a literature review of cases published to date and present a new case in which osteochondroma originating in the coronoid process was associated with the formation of a cyst at the body of the zygoma, necessitating the reconstruction of the body of the zygoma.