[The effect of zinc chloride mouthwashes on caries-inducing plaque streptococci. 3. The antibacterial effect of zinc chloride on the species Str. mutans, Str. sanguis and Str. salivarius in dental plaque].

The quantitative behaviour of Streptococcus mutans, Streptococcus sanguis and Streptococcus salivarius has been examined in initial findings and after application of 0.4% zinc chloride solution. After a 7 day rinsing the number of colony developing units of the species Streptococcus mutans and Streptococcus sanguis in the plaque decreased to about 30% of the determined initial values. The proportions of the species Streptococcus mutans and Streptococcus sanguis in the total streptococcus flora of the dental plaque were not changed by zinc chloride solution. The percentage of the Streptococcus salivarius increased significantly from 1% to 4% of the total number of streptococci.