Unusual causes of trismus: a report of two cases.

Chronic inability to achieve normal mouth opening can be a symptom of several diseases. Mostly the causes of inability to open mouth are articular and sometimes the cause may be extra-articular. In the two cases which are being reported in this article the causes of limited mouth opening are extra-articular and that too from rare pathologies, of which one case is of OKC of the coronoid process and the other case is of myositis ossificans of the buccinator and medial pterygoid muscle. Both the cases had adequate mouth opening both intraoperatively and at long term follow up.