Uptake of KOH-soluble and KOH-insoluble fluoride in sound human enamel after topical application of a fluoride varnish (Duraphat) or a neutral 2% NaF solution in vitro.
The uptake of alkali-soluble fluoride (calcium fluoride-like material and adsorbed fluoride) and alkali-insoluble fluoride (apatitically bound fluoride) on sound human enamel from treatment with Duraphat or a neutral 2% NaF solution was investigated in vitro. Blocks from impacted third molars were used. More fluoride was deposited on the enamel from the neutral 2% NaF solution than from the Duraphat treatment. All the fluoride could be dissolved in alkali. Globules of calcium fluoride-like material were demonstrated by scanning electron microscopy. Chemical analysis showed no measurable increase in the apatitically bound fluoride (alkali-insoluble fluoride) after brief exposures. Duraphat-treated samples submerged in water after the exposure lost only about 50% of the deposited fluoride, whereas samples treated with 2% NaF are known to lose all their fluoride under similar circumstances, a condition which may be related to the favorable clinical effect of Duraphat.
Cruz
R
R
Department of Preventive Dentistry, Faculty of Dentistry, State University of Rio de Janeiro, Brazil.
Ogaard
B
B
Rölla
G
G
D000134:Acid Etching, Dental; D000327:Adsorption; D001031:Apatites / Q000737:chemistry; D002124:Calcium Fluoride / Q000737:chemistry; D003743:Dental Enamel / Q000378:metabolism* / Q000648:ultrastructure; D005459:Fluorides / Q000737:chemistry / Q000493:pharmacokinetics*; D005460:Fluorides, Topical / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics*; D006801:Humans; D006878:Hydroxides / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D011188:Potassium / Q000737:chemistry*; D017680:Potassium Compounds; D012969:Sodium Fluoride / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics*; D012995:Solubility
D001031:Apatites; D005460:Fluorides, Topical; D006878:Hydroxides; D017680:Potassium Compounds; C023807:sodium fluoride topical preparation; D012969:Sodium Fluoride; C025105:fluorapatite; D002124:Calcium Fluoride; D005459:Fluorides; D011188:Potassium; C029943:potassium hydroxide