Abstract
Toothbrushing is the most fundamental to control periodontal disease. The purpose of this study was to evaluate the effect of toothbrushing alone on the composition of subgingival microbial flora by darkfield microscopy.
Fourteen subjects with periodontal disease were selected for this study. Clinical and microbiological monitoring was carried out before and about 1 month after oral hygiene instruction. With a clean curette, samples of subgingival bacteria were collected from 39 periodontal pockets which could be probed to 4mm or more, and were examined immediately by darkfield microscopy. On each slide, 200 bacteria were counted and classified on a percentage basis into one of the following categories; (1) coccoid cells, (2) spirochetes, (3) motile rods and (4) others. For each area sampled, the following clinical criteria were also recorded; (1) gingival index, (2) plaque index, (3) pocket depth and (4) bleeding index.
The results indicated that toothbrushing changes the proportions of certain bacterial forms (coccoid cells and spirochetes). By toothbrushing, the percentage of coccoid cells increased significantly from 14.8% to 34.9%, while spirochetes decreased significantly from 37.3% to 18.7%. No significant changes occurred in motile rods and others. Coccoid cells were negatively correlated with all clinical parameters recorded, while spirochetes were positively.
