The effect of chlorhexidine and Octapinol®on early human plaque formation. A light and electron microscopic study

Abstract

The influence of chlorhexidine and Octapinol® on early plaque formation in humans was assessed in vivo. Three subjects with healthy gingiva were used. Plastic films were applied to the buccal surfaces of the maxillary right first premolars and plaque was allowed to form for either 4 or 24 hours. After 1 minute of plaque development, a drop of water, 1 % chlorhexidine or 1 % Octapinol was gently applied in situ; in the 24‐h experiment an additional drop was added at 12 h. In total, 76 films were obtained, with a comparable number of specimens in each of the 6 groups. The samples were processed for light and transmission electron microscopy, using standardized techniques for area sampling and cell counting. All control films were covered by a surface coating of acellular material in or on which bacteria, epithelial cells and leukocytes were observed. The controls and to a lesser extent the Octapinol samples exhibited a significant increase in bacterial count between 4 and 24 h. However, the number of bacteria in the chlorhexidine samples showed only a slight increase within this period. Some microorganisms in the chlorhexidine samples appeared to be undergoing degeneration. In the Octapinol specimens the bacterial morphology was generally intact with many extracellular areas of high electron density. Chlorhexidine and Octapinol both had a qualitative effect on early plaque formation, but only the former had a detectable quantitative effect at this initial stage of plaque accumulation.