The value of three-dimensional imaging in the detection of a case of double pathology in the right maxilla of a patient.

A 14-year-old Black female was referred for management of an asymptomatic swelling in her right maxilla. The lesion measured 3cm across, was localised lateral to the right ala of the nose, felt bony hard in some areas and soft in others, and was continuous with the maxillary buccal plate. It occupied the right anterior vestibule but there was no palatal expansion. A panoramic radiograph showed a radiopaque lesion surrounded by a radiolucent periphery, but a lack of clarity prompted a computed tomographic scan. The latter revealed two separate lesions, one buccal and one palatal. The buccal lesion showed a well-defined radiolucency containing a radiopaque mass while the palatal lesion showed a small cystic area attached to the neck of an impacted tooth. Differential diagnoses of calcifying odontogenic cyst, adenomatoid odontogenic tumour or ameloblastic fibroodontoma and dentigerous cyst or odontogenic keratocyst were considered for the two lesions respectively. Enucleation of the buccal lesion and removal of the impacted tooth together with the overlying cyst presented no problem. Histologically the lesions were respectively diagnosed as a calcifying odontogenic cyst and a dentigerous cyst. Histological features are briefly described together with an historical review of the calcifying odontogenic cyst which has evoked much interest and controversy over the past five decades.