Adenomatoid odontogenic tumor associated with a dentigerous cyst

Adenomatoid odontogenic tumor (AOT) is a relatively uncommon benign lesion of odontogenic origin mainly affecting females in second decade of life, having a predilection for the anterior region of the maxilla. Histologically, it is composed of odontogenic epithelium in a variety of histopathological patterns in a mature, fibrous connective tissue stroma and characterized by slow but progressive growth. Very few cases of AOT associated with a dentigerous cyst have been reported in the literature. PubMed and Medline data showed a total of 11 cases of AOT associated with a dentigerous cyst in the literature. We present an additional case of an AOT arising from a dentigerous cyst around the crown of an unerupted upper canine in a 20-year-old female, which was clinically diagnosed as a dentigerous cyst. Histologically, the case showed proliferation of odontogenic epithelium in the form of whorls and islands typical of AOT associated with dentigerous cyst appearing thin reduced enamel like epithelium lining the cystic cavity, described previously. However, it is unclear whether this entity has a more aggressive potential.