The effect of supragingival plaque control on the composition of the subgingival microflora in human periodontitis.

The aim of this study was to evaluate the effect of supragingival plaque control on the composition of the subgingival microflora. 8 subjects with moderate to severe periodontitis were chosen for the study. Sites with periodontal destruction (GI greater than 2; probing depth greater than 6.5 mm; vertical alveolar bone loss on radiographs) were submitted to professional plaque control 3 X a week for 3 weeks. Contralateral sites received no prophylaxis and served as controls. Patients maintained usual oral hygiene during the observation period: it consisted exclusively of tooth brushing once or twice a day with no use of interdental cleaning aids. Clinical examination and bacterial sampling were performed every week. At the end of the study, PlI scores for the experimental sites showed a marked diminution compared with the control sites. No variations were observed in GI or probing depth in test or control sites during the study. The composition of subgingival plaque in both groups showed no significant variations during that period.