Prevalence of periodontal pathogens in subgingival lesions, atherosclerotic plaques and healthy blood vessels: a preliminary study

Background and Objective: Previous studies have reported different periodontal bacteria in atherosclerotic lesions, but their involvement in plaque formation remains unclear. The aim of the present study was to investigate the presence of 20 periodontal bacteria in atherosclerotic samples and healthy blood vessels (used as controls) and to clarify their relationship in regard to clinical and bacteriological periodontal status. Material and Methods: The day before vascular surgery the patients had a thorough periodontal examination and bacteriological samples were taken from periodontally diseased sites. Atheromatous plaques, internal mammary arteries and saphenous veins were harvested during surgery. A DNA-DNA hybridization procedure was used to screen periodontal and vascular samples for the 20 selected bacterial species. Results: Periodontal samples from the severe periodontitis group were found to have a higher prevalence and biomass of bacterial species than the moderate periodontitis group. In vessel samples, the prevalence of the same 20 bacterial species analyzed together was similar in the two groups, except for saphenous veins. Conclusion: The presence of periodontal pathogens in atherosclerotic plaques and in apparently healthy vessels appeared to reflect a higher level of bacteremia rather than infection of endothelial cells.