Background: Dentigerous cyst is an odontogenic cyst commonly seen arising from the impacted mandibular third molars. The epithelial lining of Dentigerous cyst may transform into an odontogenic neoplasm- like ameloblastoma. Very few cases of Adenomatoid odontogenic tumor (AOT) developing as a complication in Dentigerous cyst have been reported in literature and it has been termed as- Hybrid variant of AOT. AOT is a benign tumor of odontogenic origin composed of odontogenic epithelium presenting in diverse histopathological patterns. These lesions are usually solid but are occasionally cystic. It is generally found in young females in anterior maxilla in association with an unerupted tooth. Here we present a rare case of simultaneous occurrence of both Dentigerios cyst and AOT in a patient and review the literature on this “hybrid variant” with special emphasis on its pathogenesis. Methods: PubMed and Medline data was thoroughly researched for Hybrid variant of AOT/ AOT developing as a complication in Dentigerous cyst. Results: Only 12 cases of AOT associated with Dentigerous cysts were found in literature. Case Description: A 12 year female patient with chief complaint of swelling in anterior maxilla for past 10 months was found to have radiolucency around an impacted canine. The lesion was surgically removed and microscopic examination revealed the presence of luminal proliferations of AOT in dentigerous cyst. Conclusion: This case was diagnosed as Hybrid AOT which is a rare variant. Documentation of such cases is imperative to determine incidence, sexual predilection, age of incidence and understanding pathogenesis of this distinct variant.
Key words: AOT, Hybrid AOT, AOT developing in dentigerous cyst.