A 6-month home usage trial of a 1% chlorhexidine toothpaste (II). Effects on the oral microflora.

The effects of 1% chlorhexidine and 1% chlorhexidine/fluoride dentifrices on supragingival plaque flora were investigated in a 6-month home-usage study. 146 subjects were studied from whom plaque around 6 teeth was collected at baseline, 6 weeks and 24 weeks. Total anaerobic counts were reduced at 6 and 24 weeks in both active groups compared to control. No differences were seen in any other bacterial parameters. There was a significant decrease in the susceptibility to chlorhexidine of bacteria recovered from the subjects on the active treatments compared to control but, since the magnitude of effect was less than one dilution, this was not thought to be of any clinical significance.