Dentinoma: A Report of 2 Cases

Abstract

Dentinoma is a rare odontogenic tumor. Four histologic variants have been reported: immature dentinoma (containing tubular dentine, dysplastic dentine, or dentinoid and odontogenic epithelium), mature dentinoma (immature dentinoma without epithelium), ameloblastic fibrodentinoma (ameloblastic fibroma-like tumors with tubular dentine or dentinoid), and adenomatoid dentinoma. We present 2 cases of dentinoma. The first patient was an 8-year-old boy with an ill-defined multilocular radiolucent/radiopaque lesion overlying unerupted teeth 13 and 14. The lesion was curetted. Histopathologically, the biopsy contained abundant hyalinized, eosinophilic material in a vaguely lobular configuration, with entrapped islands of benign odontogenic epithelium as well as stellate and spindled cells. The odontogenic epithelium was present in small and large islands and in strands. Two years later, there was a persistent radiolucency at the site, and this area was re-curetted. This showed typical deposits of dentinoid with entrapped odontogenic epithelium and stellate and spindled cells. Tubular dentine, enamel matrix, and ghost cells were not identified in either specimen. The second patient was a 12-year-old girl with a well-defined radiolucency in the mandible associated with the crown of an unerupted left second molar. The histopathology was identical to that of the re-curetted lesion from case 1. The nature of dentinoid is still poorly understood; it is likely a product from an abnormal epithelial-mesenchymal interaction of tooth development. Ameloblastic fibrodentinoma and dentinogenic ghost cell tumor are found in the category of “odontogenic epithelium with odontogenic ectomesenchyme” under the World Health Organization classification. The category under which dentinoma belongs is still controversial.