Internal Dental Fistula by Periapical Lesion in a California Sea Lion

Abstract

A 5-year, 9-month-old female California sea lion (Zalophus califomianus) began feeding poorly five months ago. It presented with swelling in front of the right orbit and drainage from the gingival mucosa in the right maxillary canine part. The swelling was improved by administration of an antibiotic and feeding also resumed. However, a relapse subsequently occurred. Because bone resorption was observed around the root apex of the maxillary right canine in a radiographic examination under husbandry training, an anesthetic chamber by isoflurane was introduced, and general anesthesia was maintained after intubation. Oral examination and treatment were then performed. Oral examination revealed pulp exposure from wear in many teeth. A fistula was recognized in the buccal gingival mucosa where the root apex of the maxillary right canine was located. When the maxillary right canine and all teeth with exposed, dental pulp was extracted and the sockets curetted, and the socket of the right maxillary canine and the fistula were penetrated. Therefore, this case was diagnosed as an internal dental fistula by periapical lesion of this tooth. Ten months after the operation the sea lion was in good condition. There are many pulp exposures by attrition in large exhibit animals. Improvement of the rearing environment, and diagnosis and treatment by routine oral and radiographic examination are therefore necessary.