title: [A two-year randomized clinical trial of 1.23% fluoride foam on dental caries increment in primary teeth].
abstract: OBJECTIVE
  To evaluate the effect of bi-annual professional application of 1.23% fluoride foam on caries reduction in the primary dentition over a two-year period.
  
  
  METHODS
  In a double-blind, cluster-randomised, placebo-controlled trial, 392 children aged 3 - 4 years from 15 classes were randomly assigned to two groups on a school class basis. The experimental group (8 classes) received a bi-annual fluoride foam application, and the placebo control group (7 classes) received the placebo. The analysis of caries increment was based on the class as the unit of analysis. The independent-samples t tests were performed to compare the differences in caries indices at baseline and caries increments between the two groups.
  
  
  RESULTS
  The mean caries increment in foam group was 3.8 dmfs while it was 5.0 dmfs in the placebo control group, resulting in 24.2% caries reduction (P < 0.05). The experimental group had a 37.6% caries reduction on approximal surfaces compared with the placebo control group (P < 0.01). Although the mean dmfs increment of bucco-lingual surfaces was lower in the experimental group than that in the control group, it was not statistically significant (P > 0.05). No significant difference in the mean caries increment was observed on occlusal surfaces between the two groups (P > 0.05).
  
  
  CONCLUSIONS
  Bi-annual professional application of fluoride foam was effective in reducing the increment of dental caries in the primary teeth.
authors.affiliation: Key Laboratory for Oral Biomedical Engineering of Ministry of Education, School of Stomatology, Wuhan University, Wuhan 430079, China.
authors.forename: Han
authors.initials: H
authors.lastname: Jiang
authors.forename: Bao-jun
authors.initials: BJ
authors.lastname: Tai
authors.forename: Min-quan
authors.initials: MQ
authors.lastname: DU
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Ying
authors.initials: Y
authors.lastname: Guo
mesh_terms: D002327:Cariostatic Agents / Q000008:administration & dosage* / Q000627:therapeutic use; D002675:Child, Preschool; D003731:Dental Caries / Q000517:prevention & control*; D004311:Double-Blind Method; D005260:Female; D005459:Fluorides / Q000008:administration & dosage* / Q000627:therapeutic use; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D014094:Tooth, Deciduous
chemical_list: D002327:Cariostatic Agents; D005459:Fluorides