title: Urinary fluoride excretion after application of fluoride varnish and use of fluoride toothpaste in young children.
abstract: BACKGROUND
  The efficacy and safety of combined use of topical fluoride products are essential issues that must be monitored.
  
  
  OBJECTIVE
  To assess urinary excretion of fluoride after application of two different dental varnishes containing 2.26% fluoride in 3- to 4-year-old children and to compare the levels with and without parallel use of fluoride toothpaste.
  
  
  METHODS
  Fifteen healthy children were enrolled to a randomized crossover trial that was performed in two parts: Part I with twice-daily tooth brushing with fluoride toothpaste and Part II with twice-daily brushing with a non-fluoride toothpaste. After a 1-week run-in period, 0.1 mL of the two fluoride varnishes (Duraphat and Profluorid Varnish) was topically applied in a randomized order. Baseline and experimental urine was collected during 6-h periods. The fluoride content was determined with an ion-sensitive electrode.
  
  
  RESULTS
  There was a statistically significant increase in the 6-h fluoride excretion after application of both experimental varnishes, with and without parallel use of fluoride toothpaste (P < 0.01). When fluoridated toothpaste was used, the mean fluoride excretion was 0.20 mg/6 h after application of Duraphat and 0.29 mg/6 h after application of Profluorid Varnish (P = 0.18).
  
  
  CONCLUSIONS
  Topical applications of 0.1 mL of fluoride varnish significantly increased the 6-h fluoride excretion. As some individuals displayed excretion levels exceeding the optimal fluoride exposure, a restricted use of fluoride toothpaste in connection with the varnish applications would decrease fluoride exposure.
authors.affiliation: Department of Odontology, Pediatric Dentistry, Umeå University, Umeå, Sweden.
authors.forename: Frida
authors.initials: F
authors.lastname: Lockner
authors.affiliation: Department of Odontology, Cariology and Endodontics, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Svante
authors.initials: S
authors.lastname: Twetman
authors.affiliation: Department of Odontology, Pediatric Dentistry, Umeå University, Umeå, Sweden.
authors.forename: Christina
authors.initials: C
authors.lastname: Stecksén-Blicks
mesh_terms: D002675:Child, Preschool; D018592:Cross-Over Studies; D005459:Fluorides / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000652:urine*; D005460:Fluorides, Topical / Q000008:administration & dosage* / Q000493:pharmacokinetics; D006801:Humans; D012969:Sodium Fluoride / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000652:urine; D014100:Toothpastes / Q000737:chemistry*
chemical_list: D005460:Fluorides, Topical; D014100:Toothpastes; C023807:sodium fluoride topical preparation; D012969:Sodium Fluoride; D005459:Fluorides