Neoplasia masquerading as periapical infection.

Seven examples of neoplasia which presented as periapical radiolucencies are described. These were all initially treated for presumed periapical infection. The atypical features that should alert dentists to the possibility of a tumour presenting in this manner are: a vital tooth with minimal caries, root resorption and an irregular radiolucent outline, tooth mobility in the absence of generalised periodontal disease, regional nerve anaesthesia, and failure to respond to good endodontic therapy. All material removed at the time of apical surgery must be examined histologically to prevent neoplasia being overlooked.