Nonbactericidal approach to reduce colonization of plaque microflora on teeth in vitro and in vivo

A non-antibacterial, surface-modifying, perfluorosulfonamidoalkyl ester of phosphorous acid (PSAEP, 1) was adsorbed to saliva-coated hydroxyapatite disks in vitro. Pretreatment of saliva-coated hydroxyapatite beads with different concentrations of 1 markedly reduced the adherence of radiolabeled Streptococcus mutans or Actinomyces viscosus when compared with the buffer-treated controls. Pretreatment of the cells with the compound also significantly impaired their subsequent attachment to saliva-coated hydroxyapatite. In a low surface-to-volume ratio adsorption model, i.e., saliva-coated hydroxapatite disks, pretreatment with 1 for 1 min markedly reduced the adsorption of A. viscosus to the disks. A 1% solution applied topically twice a day significantly (alpha = 0.05) reduced S. mutans-induced smooth and fissure caries in rats. The effect of 0.05% 1 in a rinse was also evaluated on experimental gingivitis in beagle dogs for 6 weeks. A topical application twice a day significantly (alpha = 0.05) reduced plaque-induced gingivitis when compared to that achieved with the placebo. Microbial analyses of the plaque adjacent to gingiva indicated reduction in filamentous medium and large spirochetes as compared with that seen in the pretreatment phase. Collectively, the results show that it is possible to reduce dental caries and gingivitis via an interference with the specific adsorption of organisms to teeth.