Orthokeratinized odontogenic cyst: A rare presentation

Abstract

Orthokeratinized Odontogenic Cyst (OOC) is a developmental cyst of odontogenic origin and was initially defined as the uncommon orthokeratinized variant of the Odontogenic Keratocyst (OKC), until the World Health Organization's (WHO's) classification in 2005, where it was separated from the Keratocystic Odontogenic Tumor (KCOT). It is a relatively uncommon developmental cyst comprising of only 0.4% of all odontogenic cysts. It is rather mystifying that its radiographic features are similar to the dentigerous cyst and histological characteristics are similar to the odontogenic keratocyst; and it has inconsistent cytokeratin expression profiles overlapping with both the dentigerous cyst and odontogenic keratocyst as well as with the epidermis. It has a predilection for the posterior mandibular region. This is a report of a rare case of OOC in an unusual maxillary anterior region, with emphasis on its biological characteristics.