TY - JOUR
T1 - pH-Dependent bactericidal effects of acidulated fluoride gels on preformed plaque aggregates of Streptococcus mutans 6715
AU - Caufield, P. W.
AU - Wannemuehler, Y.
PY - 1984
Y1 - 1984
N2 - The anticaries action of topically applied sodium fluoride (NaF) preparations has been attributed, at least in part, to the antibacterial effect of fluoride on cariogenic bacteria. In this report we examined the bactericidal activity of acidulated NaF gels against preformed plaque aggregates of Streptococcus mutans 6715. Both commercially available and laboratory-prepared gels were tested. Prepared NaF gels were acidified to various pH levels with HCl, H3PO4, or HF. The aggregates of S. mutans were immersed in the various fluoride gels for 5 min and then monitored for viability. None of the commercially available NaF gels with pHs of 3.5 to 4.5 and fluoride concentrations of 5,000 to 12,300 μg/ml were capable of exerting complete bactericidal activity against aggregates of S. mutans. For the laboratory-prepared NaF gels, neither the source of hydrogen ion nor the source of fluoride influenced the outcome when fluoride was present at the appropriate MBC and pH. NaF gels with a fluoride concentration of 37,000 μg/ml were bactericidal to S. mutans at pH 3.0. At pH 2.5 and 2.0, approximately 12,000 and 1.100 μg of fluoride per ml, respectively, was bactericidal. Results from this study suggest that the bactericidal properties of acidulated NaF gels can be enhanced by lowering their pHs to below 3.0.
AB - The anticaries action of topically applied sodium fluoride (NaF) preparations has been attributed, at least in part, to the antibacterial effect of fluoride on cariogenic bacteria. In this report we examined the bactericidal activity of acidulated NaF gels against preformed plaque aggregates of Streptococcus mutans 6715. Both commercially available and laboratory-prepared gels were tested. Prepared NaF gels were acidified to various pH levels with HCl, H3PO4, or HF. The aggregates of S. mutans were immersed in the various fluoride gels for 5 min and then monitored for viability. None of the commercially available NaF gels with pHs of 3.5 to 4.5 and fluoride concentrations of 5,000 to 12,300 μg/ml were capable of exerting complete bactericidal activity against aggregates of S. mutans. For the laboratory-prepared NaF gels, neither the source of hydrogen ion nor the source of fluoride influenced the outcome when fluoride was present at the appropriate MBC and pH. NaF gels with a fluoride concentration of 37,000 μg/ml were bactericidal to S. mutans at pH 3.0. At pH 2.5 and 2.0, approximately 12,000 and 1.100 μg of fluoride per ml, respectively, was bactericidal. Results from this study suggest that the bactericidal properties of acidulated NaF gels can be enhanced by lowering their pHs to below 3.0.
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U2 - 10.1128/AAC.26.6.807
DO - 10.1128/AAC.26.6.807
M3 - Article
C2 - 6524898
AN - SCOPUS:0021689331
SN - 0066-4804
VL - 26
SP - 807
EP - 810
JO - Antimicrobial agents and chemotherapy
JF - Antimicrobial agents and chemotherapy
IS - 6
ER -