Bilateral coronoid hyperplasia: an important cause of restricted mandibular motion.

The diagnosis of coronoid hyperplasia relies on clinical history as well as physical findings. A history of slowly progressive limitation of motion should heighten one's index of suspicion that the limitation may not necessarily be due to a simple muscular disorder or a disorder involving the temporomandibular joint per se. Absence of a history of internal derangement is an important consideration. Simple screening films should be employed prior to subjecting the patient to more detailed studies. A panogram and Waters' projection of the mid-face are quite diagnostic. Utilization of tomography, arthrography, and magnetic resonance imaging should be considered only after appropriate screening films have been reviewed.