[Effect of supragingival plaque control on subgingival microflora and periodontal tissues]

The aim of this study was to investigate, clinically and microbiologically, forty-four sites in 11 patients presenting with generalized chronic periodontitis. Plaque Index (PI), Gingival Index (GI), Probing Bleeding (PB), Probing Depth (PD) and Insertion Level (IL) were registered. Samples of subgingival plaque were collected in the same sites for cultivation of anaerobic bacteria and determination of microbiological morphotypes using dark field microscopy. Clinical and microbiological data were recorded on the baseline and 4 weeks after the adoption of a program to control supragingival plaque and calculus. The microbiological analysis categorized the degree of development as follows: 0--not detected, 1--scarce, 2--moderate and 3--abundant. The clinical results at the baseline and on the 28th day were, respectively: PI--1.73 +/- 0.10 and 0.30 +/- 0.08; GI--1.73 +/- 0.08 and 1.41 +/- 0.08; PB--0.91 +/- 0.04 and 0.59 +/- 0.07; PD--6.43 +/- 0.20 and 5.77 +/- 0.25; and IL--6.86 +/- 0.32 and 6.52 +/- 0.34. There was significant decrease in PI, GI, PB and PD. However, the difference in IL was not significant. The relative proportions of the microbial morphotypes observed under dark field microscopy at the baseline and on the 28th day were, respectively: coccoid cells--21.16 +/- 3.77 and 36.00 +/- 4.66; mobile bacillus--44.86 +/- 2.65 and 39.50 +/- 2.64; and total treponemes--24.66 +/- 3.08 and 19.25 +/- 2.75. The cultures presented, at the baseline and on the 28th day, respectively: Prevotella intermedia/nigrescens (Pi/n)--1.36 +/- 0.18 and 0.43 +/- 0.11; Porphyromonas gingivalis--0.48 +/- 0.16 and 0.32 +/- 0.13; Actinobacillus actinomycetemcomitans--0.23 +/- 0.09 and 0.23 +/- 0.10; Fusobacterium nucleatum--0.32 +/- 0.14 and 0.41 +/- 0.13; and peptostreptococci--0.82 +/- 0.19 and 0.54 +/- 0.16. There was a significant increase in the number of coccoid cells and a decrease in the number of treponemes and Pi/n.