Plaque inhibiting effect of combinations of chlorhexidine and the metal ions zinc and tin. A preliminary report.

Rinsing experiments with combinations of chlorhexidine, zinc- and stannous ions were performed in a group of students. Chlorhexidine and zinc (0.2% and 0.3% respectively) gave a plaque inhibiting effect slightly better than chlorhexidine alone, whereas chlorhexidine and stannous ions in the same concentrations showed a reduced effect, presumably due to the low pH of the solution. Pre-rinses with metal ions caused a marked reduction in the effect of chlorhexidine, whereas chlorhexidine first and metal ions afterwards gave approximately the same effect as chlorhexidine alone. The results indicate that the metal ions and chlorhexidine have the same receptor sites in the oral cavity, chlorhexidine exhibiting the stronger affinity when the ions were applied together.