The effect of periodontal treatment on periodontal bacteria on the oral mucous membranes.

The aim of this study was to investigate the effect of conventional periodontal treatment on the prevalence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia on oral mucous membranes in patients with periodontitis. Fifteen patients were selected with moderate to severe periodontitis (mean age: 39.8 years, range: 26 to 58). From each patient the 4 deepest sites with bleeding on probing were selected for clinical and microbiological evaluation. At baseline, 6 weeks after oral hygiene instruction and extensive scaling and root planing, and 3 months after periodontal surgery, clinical parameters and microbiological samples including saliva, oral mucous membranes, and supra- and subgingival plaque were evaluated for the presence of the 3 test bacteria using indirect immunofluorescence. All clinical variables, except redness, showed a significant improvement after surgery. After treatment, the subgingival prevalence of the 3 putative periodontal pathogens had decreased significantly. However, almost no concomitant reduction in the prevalence of the bacteria was seen on the oral mucous membranes. This suggests that the oral mucous membranes may serve as a source for reinfection of the periodontium after treatment.