Odontogenic keratocyst of the maxilla presenting as periodontal abscess.

This is a case report of an odontogenic keratocyst of the maxilla initially diagnosed and treated as a periodontal abscess. The occurrence of odontogenic keratocyst in the maxilla with involvement of the antrum is relatively rare. The radiological appearance of this lesion on both conventional and panoramic radiography can be misinterpreted and emphasizes the usefulness of the computed tomography in this region.