Dental health status and endodontic treatment of captive brown bears (Ursus arctos ssp.) living in the Bernese bear pit

The teeth of five adult captive brown bears (Ursus arctos ssp.) were examined and radiographed for occlusion, loss of teeth, dental plaque and calculus, and attrition under general anesthesia. Deposits of dental calculus were found in various locations with an overall prevalence of 8% to 15% of all tooth surfaces. In all five animals, severe enamel and dentinal attrition defects were observed in canine teeth with exposed pulp. Cage-chewing behavior is probably the main cause for the dental attrition. The composition of the food and feeding management are most likely responsible for the lack of natural cleaning and the resulting plaque and calculus formation. All affected canine teeth were treated with endodontic procedures using several materials and techniques, and evaluated one- to two-and-a-half years later by clinical examination, radiography, and scanning electron microscopy of silicone casts of the treated teeth. All coronal fillings were tight. The apices were not completely sealed in two teeth. We conclude that the use of adequate and specialized instrumentation and techniques for the treatment of these long, curved, large diameter root canals is more important than the particular endodontic and restorative materials used. The dental health status of zoo animals is an indicator of their general well-being. Preventive measures should be taken in their environment and management to minimize the risk of dental conditions.