A seven year old, female intact, Yorkshire Terrier was referred to the Cornell Dentistry and Oral Surgery Service for further evaluation of an oral mass first noted one and a half years prior to referral. The mass had recently noted to be growing and displacing the right third maxillary premolar {107). Past pertinent medical history included stable chronic renal disease. The patient was not currently being treated with any medications. Oral examination revealed a 7mm x 5mm red, verrucous mass between 107 and 108; the mass appeared to arise from the buccal gingiva at 107, extending medially to involve the hard palate and causing rotation of 107. The patient was reportedly clinically unaffected by the mass, and physical exam was otherwise unremarkable. Differential diagnoses included benign versus malignant neoplasia. Complete staging revealed no evidence of metastatic disease; a skull CT and biopsy of the mass were performed, revealing an acanthomatous ameloblastoma. The patient underwent a right partial maxillectomy to resect the tumor. Recovery from surgery and anesthesia was uneventful. Four weeks postoperatively clients reported a complete return to function with excellent outcome.