title: Calcium fluoride formation on sound enamel using fluoride solutions with and without lactate.
abstract: The formation of calcium (Ca) fluoride (CaF2) on bovine enamel blocks during clinically relevant treatment times using neutral fluoride (F) solutions (0.26 mol/l F) with and without 0.1 mol/l lactate was investigated. Uncoated and pellicle-coated blocks were evaluated for alkali-soluble (1 mol/l KOH, three consecutive 24-hour treatments) Ca, PO4, and F after treatment by the F solutions for 0, 5, 15, 30, and 60 min. There was an overall time-related increase in F recovery, while Ca tended to remain at baseline levels. Less F was recovered from the pellicle-coated blocks. The addition of lactate to the F treatment solution did not result in an overall increase in alkali-soluble F recovery, but did result in the formation of cuboidal shaped crystals which closely approached the morphology of pure CaF2. A 1:2 stoichiometric ratio Ca:2F (mol:mol) was not established based on chemical analyses. The ultrastructural and elemental composition of surface deposits on the samples, as determined using scanning electron microscopy, X-ray diffraction, and energy-dispersive spectroscopy, established the presence of CaF2 after 24-hour F treatments; however, it was not possible to directly demonstrate the formation of CaF2 after clinically relevant treatment times.
authors.affiliation: Department of Oral Sciences, Eastman Dental Center, Rochester, NY 14620.
authors.forename: A M
authors.initials: AM
authors.lastname: Harding
authors.forename: D T
authors.initials: DT
authors.lastname: Zero
authors.forename: J D
authors.initials: JD
authors.lastname: Featherstone
authors.forename: S M
authors.initials: SM
authors.lastname: McCormack
authors.forename: C P
authors.initials: CP
authors.lastname: Shields
authors.forename: H M
authors.initials: HM
authors.lastname: Proskin
mesh_terms: D000818:Animals; D002118:Calcium / Q000032:analysis; D002124:Calcium Fluoride / Q000032:analysis / Q000737:chemistry*; D002417:Cattle; D003741:Dental Deposits / Q000503:physiopathology; D003743:Dental Enamel / Q000648:ultrastructure*; D044622:Dental Pellicle; D004577:Electron Probe Microanalysis; D005459:Fluorides / Q000032:analysis; D006878:Hydroxides / Q000737:chemistry; D007773:Lactates / Q000008:administration & dosage / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D017680:Potassium Compounds / Q000737:chemistry; D012969:Sodium Fluoride / Q000008:administration & dosage / Q000737:chemistry*; D013997:Time Factors; D014961:X-Ray Diffraction
chemical_list: D006878:Hydroxides; D007773:Lactates; D017680:Potassium Compounds; D012969:Sodium Fluoride; D002124:Calcium Fluoride; D005459:Fluorides; D002118:Calcium; C029943:potassium hydroxide