title: Low-fluoride acidic dentifrice: a randomized clinical trial in a fluoridated area.
abstract: BACKGROUND
  Low-fluoride dentifrices have been suggested as alternatives to reduce dental fluorosis risk, but there is no consensus regarding their clinical effectiveness, which has been suggested to be increased when their pH is acidic.
  
  
  OBJECTIVE
  This single-blind randomized clinical trial evaluated the caries increment during the use of a low-fluoride acidic liquid dentifrice.
  
  
  METHODS
  Four-year-old schoolchildren (n = 1,402) living in a fluoridated area (0.6-0.8 ppm F) were randomly allocated to 4 groups differing according to the type of dentifrice used over a 20-month period. Group 1 (n = 345): liquid dentifrice, 1,100 ppm F, pH 4.5. Group 2 (n = 343): liquid dentifrice, 1,100 ppm F, pH 7.0. Group 3 (n = 354): liquid dentifrice, 550 ppm F, pH 4.5. Group 4 (n = 360): toothpaste, 1,100 ppm F, pH 7.0. At baseline and after 20 months, clinical examinations were conducted (dmfs index) and caries increment was calculated. Data were analysed by GLM procedure using classrooms (cluster) as unit of analysis (p < 0.05).
  
  
  RESULTS
  The mean ± SD (95% CI) net increments found were as follows. Group 1: 2.06 ± 2.38 (1.8-2.3); group 2: 2.08 ± 2.87 (1.7-2.4); group 3: 2.05 ± 2.79 (1.7-2.4), and group 4: 2.08 ± 2.34 (1.8-2.4). No significant differences were detected among the groups.
  
  
  CONCLUSIONS
  In a population with high caries risk living in a fluoridated area, as the selected sample, and according to the present protocol, the low-fluoride acidic liquid dentifrice seems to lead to similar caries progression rates as conventional 1,100 ppm F toothpaste.
authors.affiliation: Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil.
authors.forename: F V
authors.initials: FV
authors.lastname: Vilhena
authors.forename: K P K
authors.initials: KP
authors.lastname: Olympio
authors.forename: J R P
authors.initials: JR
authors.lastname: Lauris
authors.forename: A C B
authors.initials: AC
authors.lastname: Delbem
authors.forename: M A R
authors.initials: MA
authors.lastname: Buzalaf
mesh_terms: D000143:Acids; D001938:Brazil; D002327:Cariostatic Agents / Q000008:administration & dosage*; D002675:Child, Preschool; D004245:DMF Index; D003731:Dental Caries / Q000517:prevention & control; D003733:Dental Caries Susceptibility; D003802:Dentifrices / Q000008:administration & dosage* / Q000737:chemistry; D018450:Disease Progression; D005457:Fluoridation; D005459:Fluorides / Q000008:administration & dosage*; D005500:Follow-Up Studies; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008137:Longitudinal Studies; D016037:Single-Blind Method
chemical_list: D000143:Acids; D002327:Cariostatic Agents; D003802:Dentifrices; D005459:Fluorides