ACTION OF SODIUM-FLUORIDE ON PHAGOCYTOSIS BY SYSTEMIC POLYMORPHONUCLEAR LEUKOCYTES

Alterations in phagocytosis appear to be important in the onset and de velopment of periodontitis. We investigated new substances that may be of use in the treatment of periodontitis. In a preliminary study, we tested the effect of sodium fluoride on phagocytosis by circulating po lymorphonuclear leucocytes (PMNs) in 10 replicate assays using blood f rom six healthy subjects. Sodium fluoride was tested at concentrations of 1.0 mu m to 4.0 mu m against Streptococcus oralis, Streptococcus m utans, Streptococcus sobrinus and Streptococcus sanguis. The phagocyti c index against all microorganisms increased significantly at all conc entrations of sodium fluoride assayed; this effect was dose dependent. Sodium fluoride appeared to stimulate phagocytosis via two mechanisms : an apparent increase in bacterial susceptibility to phagocytosis, an d direct stimulation of phagocytosis by PMNs.