Orthokeratinized odontogenic cyst (OOC) was first identified as the rare variant of keratocystic odontogenic tumor (KCOT) for its different histopathology and rare recurrence which was reclassified by WHO in 2005. The orthokeratinized odontogenic cyst is a distinct clinicopathologic entity and is histologically characterized by a thin, uniform, epithelial lining with orthokeratinization and a subjacent granular cell layer. The basal cells are usually cuboidal or flattened. OOC in maxilla is rare. This article presents a case of 56-years-old male patient with OOC in left maxilla. The clinical, radiographic and histological features of the cyst are discussed in this case report.

Orthokeratinized odontogenic cyst (OOC) was first identified as the rare variant of keratocystic odontogenic tumor (KCOT) for its different histopathology and rare recurrence which was reclassified by WHO in 2005. The orthokeratinized odontogenic cyst is a distinct clinicopathologic entity and is histologically characterized by a thin, uniform, epithelial lining with orthokeratinization and a subjacent granular cell layer. The basal cells are usually cuboidal or flattened. OOC in maxilla is rare. This article presents a case of 56-years-old male patient with OOC in left maxilla. The clinical, radiographic and histological features of the cyst are discussed in this case report.