Clinical Study of Plaque Accumulation Influencing Gingival Tissue

It has been reported by a number of studies that bacterial plaque is a major etiologic factor in periodontal disease. The purpose of the present study was to clear the relationship between a rapid plaque formation after toothbrushing withdrawal and subclinical gingival inflammation and to observe microbial population shifts in developing supragingival plaque. The facial and lingual areas of six selected teeth (6/41|14/6) were assessed in a total of 40 dental students with normal dentition and a clinically healthy gingiva. The subjects were at randam divided into four groups. After a thoroughly plaque removal, the selected teeth were photographed under a standardized condition and gingival exudate measurements were undertaken on the upper three teeth (6|14). Subsequent to the first examination the subjects were given instructions not to brush their teeth for 12, 24, 48 and 72 hours respectively. They were rechecked each time and after the plaque samples were collected from the other areas except the selected teeth, bacterial smears were prepared. The selected teeth were photographed in the same criteria as the first examination following application of a disclosing solution (MT-1000) and the stained area on photograph was examined planimetrically. The results were as follows: 1) When compared upper teeth with lowers, plaque accumulated slowly on lower teeth, while in the buccal side of upper teeth the plaque accumulation was remarkably high in order of 6, 4, 6, 1, 4 and 1 since 48 hours toothbrushig withdrawal and in the lingual side a significant increase in plaque accumulation was observed in order of 6, 4, 1, 6, 4 and 1 at 72 hours toothbrushing withdrawal. 2) The more increase in gingival exudate amounts was found in the buccal side than the lingual side of all the teeth. There was a significant increase in gingival exudate amounts of all the teeth except 4 since 48 hours toothbrushing withdrawal. A close correlation between plaque accumulation and gingival exudate amounts was demonstrated. 3) Predominant microorganisms were Gram positive cocci being decreased throughout the experimental periods. The frequency in Gram negative cocci and Gram positive rods did not change, whereas Gram negative rods and filaments had a tendency to increase with plaque age.