title: Effect of fluoride on glucose incorporation and metabolism in biofilm cells of Streptococcus mutans.
abstract: The aim of this study was two-fold: firstly, to study the effect of high fluoride concentrations on carbohydrate metabolism in Streptococcus mutans present in biofilms on hydroxyapatite; and, secondly, to evaluate the effect of fluoride-bound hydroxyapatite on lactic acid formation in growing biofilms of Strep. mutans. Biofilms of a clinical strain of Strep. mutans on saliva-coated hydroxyapatite beads were incubated with sodium fluoride over a wide range of concentrations. At high fluoride concentrations (>10 mM) the incorporation of [14C]-labeled glucose decreased by 80-85%, at both pH 7.0 and 5.6. At lower fluoride concentrations, the effect of fluoride on the incorporation of labeled glucose was pH-dependent in both biofilm cells and in planktonic cells. At pH 7.0, fluoride at concentrations < 10 mM had little or no effect. Pretreatment of hydroxyapatite discs with fluoride varnish (Fluor Protector) or fluoride solutions caused a statistically significant reduction of lactic acid formation in associated, growing biofilms of Strep. mutans. Fluoride varnish and 0.2% (47.6 mM) sodium fluoride solution exhibited a statistically significant inhibitory effect on lactate production.
authors.affiliation: Department of Immunology, Microbiology, Pathology and Infectious Diseases, Huddinge University Hospital, Sweden. susann.balzar-ekenback.oo@net.ptj.se
authors.forename: S
authors.initials: S
authors.lastname: Balzar Ekenbäck
authors.forename: L E
authors.initials: LE
authors.lastname: Linder
authors.forename: M L
authors.initials: ML
authors.lastname: Sund
authors.forename: H
authors.initials: H
authors.lastname: Lönnies
mesh_terms: D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D002250:Carbon Radioisotopes; D002327:Cariostatic Agents / Q000737:chemistry / Q000494:pharmacology*; D004338:Drug Combinations; D017886:Durapatite / Q000737:chemistry; D005459:Fluorides / Q000737:chemistry / Q000494:pharmacology*; D005460:Fluorides, Topical / Q000737:chemistry / Q000494:pharmacology; D005947:Glucose / Q000378:metabolism* / Q000493:pharmacokinetics; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000037:antagonists & inhibitors / Q000378:metabolism; D011140:Polyurethanes / Q000737:chemistry / Q000494:pharmacology; D019275:Radiopharmaceuticals; D012463:Saliva / Q000502:physiology; D012821:Silanes / Q000737:chemistry / Q000494:pharmacology; D012969:Sodium Fluoride / Q000737:chemistry / Q000494:pharmacology; D013295:Streptococcus mutans / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D013499:Surface Properties
chemical_list: D002250:Carbon Radioisotopes; D002327:Cariostatic Agents; D004338:Drug Combinations; D005460:Fluorides, Topical; D011140:Polyurethanes; D019275:Radiopharmaceuticals; D012821:Silanes; D019344:Lactic Acid; C022599:Fluor Protector; D012969:Sodium Fluoride; D017886:Durapatite; D005947:Glucose; D005459:Fluorides