Mixed odontogenic tumors in four young dogs: ameloblastic fibroma and ameloblastic fibro-odontoma

Maxillary Cystic Ameloblastic Fibroma in a Dalmatian Mix

A 6-month-old intact male Dalmatian mix puppy was presented for the evaluation of left maxillary swelling due to a suspected cyst and an unerupted left maxillary canine tooth. Removal of the unerupted left maxillary canine tooth (204) and enucleation of the cyst was performed, followed by histological analysis, which identified the maxillary swelling to be a cystic ameloblastic fibroma. Ameloblastic fibromas are rare in companion animals, and to the best of the authors' knowledge, this is the first cystic variant reported in dogs. The clinical, radiographic, cone beam computed tomography, and histological findings of this case are discussed and compared with the findings of previously documented human and domestic animal cases.

Ameloblastic Fibro-Odontoma in a Free-Ranging Rocky Mountain Bighorn Sheep (Ovis canadensis canadensis), Alberta, Canada

An adult female Rocky Mountain bighorn sheep (Ovis canadensis canadensis) was euthanized because of a large mandibular mass. Histopathology revealed an ameloblastic fibro-odontoma, a rare odontogenic neoplasia.

Differential diagnosis for a mandibular mass - a rare case of an odontoameloblastoma in a red deer (Cervus elaphus elaphus)

BACKGROUND

Mandibular masses caused by inflammatory processes due to bacterial infections, most common with Actinomyces bovis, are well known in herbivors. This case represents a rare differential diagnosis to common inflammatory processes which cannot be distinguished from neoplasia without detailed histopathological examination.

CASE PRESENTATION

A large unilateral mandibular mass of a free-ranging female adult red deer (Cervus elaphus elaphus) was submitted for pathological examination. The animal had been shot due to its poor body condition. Grossly, the mandibular mass showed gingival ulceration and necrosis. Histologically, irregular strands and islands of odontogenic epithelial cells and a matrix of dentin and osteoid-like material were found, leading to the diagnosis of an odontogenic tumor. Considering the animal's age the tumor was classified as odontoameloblastoma with secondary chronic purulent osteomyelitis.

CONCLUSIONS

Odontogenic tumors are rare in domestic and wildlife species and so far have not been reported in red deer. In addition to the more common inflammatory processes of the mandibula and other neoplastic diseases of the oral cavity, odontogenic tumors represent a rare differential diagnosis that must be kept in mind especially when masked by inflammatory lesions.