A short-term study of the effects of SBHAN, a novel compound, on gingival inflammation in the beagle dog

Intra-oral microbial profiles of beagle dogs assessed by checkerboard DNA–DNA hybridization using human probes

Some investigators suggest a similarity between the oral microbiota of dogs and humans. The in vivo assessment of ecologic relationships among bacterial species and between bacterial species and their habitat is difficult to carry out. Consequently, this aspect is often neglected in animal oral microbiological studies. This study aimed to examine the proportions of 40 bacterial species in samples from five intra-oral habitats in beagle dogs using checkerboard DNA-DNA hybridization. Microbial samples were taken from subgingival and supra-gingival plaque, the tongue, tonsils and cheek mucosa in seven beagle dogs. Samples were individually evaluated for their content of 40 bacterial species and the percentage of total DNA probe count was determined for each species, at each habitat. All tested species could be detected in all sampled habitats but each habitat had a distinct community structure. The microbiotas colonizing the hard surfaces in the oral cavity were quite different from the microbiotas colonizing the soft tissues. Bacterial species that are in humans considered to be periodontopathogens are present in high proportions. This study underlines the importance of the habitat and the host on the local microbial profile.

Effect of different crown contours on periodontal health in dogs. Microbiological results

OBJECTIVES

In some clinical circumstances, i.e. in cases when the upper anterior region has to be restored by prosthetic means, it is necessary to place the margins of crowns and fixed partial dentures subgingivally. In addition, in periodontally compromised patients the restoration sometimes has to be overcontoured in order to replace the lost interdental papilla. The overcontoured crown margin may influence the subgingival bacterial composition. Therefore, the aim of the present investigation was to evaluate the effect of three different subgingival crown contours in dogs on the composition of the subgingival microbiota.

METHODS

In four adult beagle dogs the second and third premolars were prepared in three quadrants and restored with single gold crowns. The unprepared second and third premolars in the last quadrant served as controls. The crowns had three different emergence profiles including a normal contour, a 30 degrees and a 50 degrees over-contour. During the entire study period, professional oral hygiene was performed seven times a week. Microbiological samples were harvested from four sites of test and control teeth (mesial, distal, buccal and lingual) at baseline, after 3 months, and after 5 months.

RESULTS

The microbiological analysis (DNA-DNA hybridization technique) of the subgingival microbial flora revealed a dominance of P. intermedia, T. denticola and C. showae in all test and control groups at baseline. At three months, the total amount of bacteria increased and a broader variety of bacterial species could be detected. The detection frequency of most bacterial species increased from baseline to the 5-month evaluation. The frequency of detection of some species was higher in the 30 degrees and 50 degrees overcontoured test groups compared to the normal contour group and to the natural teeth.

CONCLUSIONS

It can be concluded within the limits of this investigation that overcontoured gold crowns placed subgingivally have only slight effects on the microbiological composition in dogs when an intensive oral hygiene regimen was executed.