Effect of Constant Diet on Microbial Populations of Human Dental Plaque.

Constant diet, minimal oral hygiene, and simulated weightlessness appeared to have no statistically significant effect on selected microbial populations of human dental plaque. Subjects were eight airmen participating in a concurrently conducted bed rest - exercise study. Oral prophylaxis and restoration of various teeth preceded the 16-week study, and minimal oral hygiene procedures were imposed. Samples were collected twice during the first week and once weekly thereafter. Standard bacteriologic plate count procedures were used to enumerate selected organisms. Total aerobes, total anaerobes, and populations of Actinomyces, Fusobacterium, Neisseria, Nocardia, and Veillonella generally tended to decrease throughout the study. Aerobic and facultative streptococci and populations of S. salivarius, Bacteroides melanogenicus, and Lactobacillus generally showed little change other than normal fluctuation. Only the weekly means for S. salivarius were significantly different for supra- and subgingival plaque. Correlation of bacterial count data with clinical observations indicate that the minimal oral hygiene procedures imposed during this study were sufficient to remove bacterial plaque and prevent shifts in predominant organisms in developing plaque, thereby maintaining the oral health status of the individual subjects. (Author)