Keratinized Odontogenic Cysts in a Malayan Tiger (Panthera tigris jacksoni)

Abstract

A 14-year-old male intact Malayan tiger (Panthera tigris jacksoni) was presented for a routine annual wellness exam and comprehensive oral health assessment and treatment, during which an odontogenic cyst was incidentally diagnosed from radiographs. Prior to a second immobilization for computed tomography (CT) and surgical removal of the cyst, the tiger developed anorexia, lethargy, and reluctance to train, which were clinical signs suspected to be reflective of pain secondary to the odontogenic cyst. A CT scan of the skull revealed 2 odontogenic cyst lesions associated with teeth 204-207 and 208-209, and associated tooth root resorption, focal lysis of the maxilla, communication with the left nasal passage, thinning of the ventral margin of the left orbit and maxillary foramen, and left mandibular lymphadenopathy. Complete enucleation of each cyst wall and surgical extraction of associated teeth were performed. Histopathologic findings were consistent with an odontogenic cyst containing keratinized stratified squamous epithelium, keratin debris within the cyst lumen, and a lymphoplasmacytic inflammatory infiltrate. Postoperatively, the tiger recovered uneventfully, clinical signs resolved within 2 weeks and have not recurred at the time of publication of this article. Similar keratinized odontogenic cysts are described in dogs, and there is only one other case report in a felid. This is the first known report of an odontogenic cyst in a tiger and of a keratinized odontogenic cyst in a nondomestic species.

Keywords: Malayan tiger; Panthera tigris jacksoni; inflammatory odontogenic cyst; keratinized odontogenic cyst; odontogenic cyst.