Abstract
Bacterial plaque has been implicated as the primary etiologie factor in inflammatory periodontal disease. The most direct evidence comes from such studies as those by Loe, Theilade, and Jensen, who examined the production of gingival inflammation in healthy adults who stopped toothbrushing and other oral hygiene procedures. These investigators showed that a group of 12 dental students developed considerable accumulations of soft debris (plaque) and clinically observable gingival inflammation when all oral hygiene measures were withdrawn. When oral hygiene procedures were reinstated and the plaque material removed, the gingivitis sub-sided. In a subsequent study, these investigators repeated their results and reported that the individual rate of gingivitis development correlated closely with the rate of plaque accumulation. During plaque formation a general increase in the number of microorganisms takes place, and in the course of a few days a definite change in the composition of the flora occurs. While these quantitative changes are taking place there is a proportional shift to more Gram negative and anaerobic organisms, but no species was found that was not a normal resident.