title: The effect of contact time of acidulated phosphate fluoride on fluoride concentration in human enamel.
abstract: Polished enamel blocks with known surface areas were obtained from human mandibular incisors. Acidulated phosphate fluoride was applied for 4 min and washed off after additional contact times of 0, 2, 6 and 24 h, respectively. The enamel fluoride concentrations were determined in three successive etch depths before and after extraction in 1 M KOH for 24 h. The predominant reaction product was CaF2. The concentration of the fluoride bound as fluorapatite or fluorhydroxyapatite reached an optimal level after a 6-h contact time.
mesh_terms: D000149:Acidulated Phosphate Fluoride / Q000378:metabolism*; D001031:Apatites / Q000378:metabolism; D002124:Calcium Fluoride / Q000378:metabolism; D003743:Dental Enamel / Q000378:metabolism*; D005459:Fluorides / Q000378:metabolism*; D006801:Humans; D006882:Hydroxyapatites / Q000378:metabolism; D066298:In Vitro Techniques; D013997:Time Factors
chemical_list: D001031:Apatites; D006882:Hydroxyapatites; D000149:Acidulated Phosphate Fluoride; C028869:fluor-hydroxylapatite; C025105:fluorapatite; D002124:Calcium Fluoride; D005459:Fluorides