title: [Effect caused by uptake of different levels of calcium to enamel fluorosis in rats].
abstract: OBJECTIVE
  To study the effects caused by uptake of different levels of calcium to dental fluorosis in rats.
  
  
  METHODS
  Weanling rats were raised on water containing 0.1 mol/L fluoride and food containing low, normal and high levels of calcium for 2 months. The concentration of fluoride in enamel was analysed by F-ion-selective electrode. The microradiographic examination and light-density analysis were performed. The enamel structure was examined under SEM.
  
  
  RESULTS
  The more calcium was ingested, the lower level of fluoride amount in enamel was observed (P < 0.01). With increasing food calcium ingestion, the light density value was decreasing, and the level of enamel mineralization was increasing (P < 0.01).
  
  
  CONCLUSIONS
  With increasing food calcium ingestion during the development of teeth, the level of dental fluorosis is decreasing. The calcium supply is effective in protection from fluoride toxicity to a certain extent.
authors.affiliation: Research Institute of Stomatology, Beijing Stomatological Hospital, Beijing 100050, China.
authors.forename: W
authors.initials: W
authors.lastname: Ouyang
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.forename: Z
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000818:Animals; D002118:Calcium / Q000008:administration & dosage*; D005459:Fluorides / Q000032:analysis; D009050:Fluorosis, Dental / Q000517:prevention & control*; D008297:Male; D051381:Rats; D017208:Rats, Wistar
chemical_list: D005459:Fluorides; D002118:Calcium