: Case History:

A 5-year-old Quarter horse gelding in good condition was brought to the wet lab for dental evaluation. A large mass of soft tissue covered the anterior portion of the incisive bone and he was missing the majority of his upper incisors. There was a slight odor in this area and the mass of soft tissue was impregnated with several tooth fragments as shown in figures 26, 27,28, and 29. The owner said the horse had suffered a traumatic trailer accident at 2 years of age that may have damaged the incisor area. An intraoral radiograph of the upper incisors also showed fragmented tooth material in this large mass of tissue.


This is an organized mass of soft tissue and dental fragments of hard dental material, encasing most of the upper incisor arcades. The mass is firm with a rubber consistency of tooth material showing in several areas of the exterior and embedded inside the tumor. These clinical findings, along with the radiographs, indicate an ameloblastoma. Tumors of this nature are usually benign and slow to develop. They are mass occupying and may interfere with mastication if the tumor is large. This horse had history of trauma 3 years prior that could account for tooth fragments and soft tissue enlargement, however the organized nature and consistency of the mass suggests a dental tumor.

Treatment:Surgical removal of these tumors should be done as soon as possible to ensure a favorable prognosis. All areas of involved tissue should be removed if possible. Radiation therapy may be of value post surgery to help prevent reoccurrence of the tumor.


Early diagnosis and surgical removal will decrease the chances of the tumor reoccurring, but as with most oral tumors, the prognosis should be guarded, and this area should be reevaluated semiannually for signs of reoccurrence.

B.W. Fletcher