Effect of SnF2, administered as mouthrinses or topically applied, on Streptococcus mutans, Streptococcus sanguis and lactobacilli in dental plaque and saliva.

Mouthrinsing with SnF2 reduced the Streptococcus mutans population in plaque and saliva and the proportion of Streptococcus sanguis in plaque. The effect was of short duration: 2 weeks after treatment the values of S. mutans in plaque and saliva were even higher than the pretreatment values. Topical SnF2 applications reduced the S. mutants population in plaque and saliva but did not reduce the proportion of S. sanguis in plaque. The effect was more prolonged : 4 weeks after treatment the S. mutans population in interproximal plaque remained significantly reduced and the salivary levels of the organism had not fully returned to pretreatment levels. Both SnF2 treatments significantly increased the salivary levels of lactobacilli. The values of lactobacilli in saliva remained significantly increased 4 weeks after the SnF2 mouthrinsing but had almost returned to pretreatment levels within 2 weeks after the topical SnF2 applications. The findings suggest that the cariogenic potential of dental plaque is differently affected depending on whether a drug is administered as a mouthrinse or is applied topically.