[Bacteriological findings for endodontical and apical molar dental diseases in the horse].

In most cases the diagnosis of any molar dental disease in horses is made at an advanced stage, so that permanent restoration of the diseased teeth is not feasible. Complications such as bacteraemia and septicaemia due to infections as a result of dentogenous sinusitis and following dentosurgical procedures have been described in human medicine and in veterinary medicine. Twenty patients were available for examination from the Clinic for Horses of the School of Veterinary Medicine Hannover with molar dental disease in upper or lower jaw. As a result of this disease the infected tooth had to be removed surgically. The aim of this study was to determine the presence of and to identify microbes in 20 patients. Swab samples were taken from infected pulpa, from dental abscesses and from involved nasal sinuses. The samples were examined microbiologically and tested for aerobes and anaerobes at the same time. Infectious agents were found in 19 of 20 horses. In all, 27 different species of infectious agents were isolated, including both aerobic and anaerobic microbes. Fifteen patients (75%) showed a mixed flora. Further differentiation indicated a preponderance of the group of gram-negative obligatory anaerobic agents isolated from a total of 17 horses. In all these samples there was a high concentration of infectious agents of these genera, the most common of which were Prevotella spp (n = 16) and Fusobacterium spp. (n = 15). Pre-surgical antibacterial therapy is recommended to reduce the risk of intra- and/or post-surgical bacteraemia and its serious consequences. In light of these microbiological results and considering the high degree of resistance among all anaerobic microbes, all patients in this study were treated with Amoxicillin.