ORAL MICROFLORA OF THE FERRET AT THE GINGIVAL SULCUS AND MUCOSA MEMBRANE IN RELATION TO LIGATURE-INDUCED PERIODONTITIS

The aim of this study was to describe, in the domestic ferret, the com position of the normal gingival sulcus and the near related mucosa mic roflora and the shift in the composition during an acute periodontal b reakdown induced by the placement of ligatures. Five animals were used . At the start of the experiment (day 0) and before the placement of t he ligatures, 2 microbiological samples were obtained from the gingiva l sulcus and the related mucosa at the mid-buccal surface of the right upper P4. The same sites were sampled on the left side, serving as co ntrol sites. On day 28, new microbiological samples were taken from th e same 4 sites. The samples were analyzed with darkfield microscopy an d with viable counts. In the darkfield analysis, on day 0, the predomi nant bacterial morphotype was cocci, ranging from 88-92%. The viable c ounts showed that nearly 100% of the total cultivable flora was compos ed of facultative anaerobic gram-negative and gram-positive rods. Past eurella spp., Corynebacterium spp. and Rothia spp. were the major comp onents of these bacterial groups. No anaerobic bacteria were detected. On day 28, cocci decreased to approximately 75% in the experimental g ingival sulcus sample, and filaments and rods increased significantly. Spirochetes remained largely unchanged during the experiment. The com position of the experimental site samples changed. There was a decreas e in the mean numbers of facultative anerobic gram-positive rods, and approximately one third of the microflora comprised anaerobic gram-neg ative rods, mainly Porphyromonas gingivalis and Fusobacterium spp. Alt hough the composition of the microflora of the ferret presented few si milarities to that described in dogs and monkeys, the anaerobic portio n of the gingival sulcus and oral mucosa microflora related to ligatur e-induced periodontitis presented microorganisms observed in experimen tal periodontitis both in dogs and monkeys as well as in human periodo ntal diseases.