The effect of various surface coatings on fluoride release from glass-ionomer cement

To protect glass-ionomer cement from moisture contamination and dehydration during initial setting, immediate application of a surface coating agent is recommended. This study compared the effect of various surface coatings on F release from glass-ionomer cement. Twenty glass-ionomer cement (Ketac Fil Aplicap) disks (4.52 cm2) were prepared from a Teflon mold. The control group was uncoated, while the experimental groups were coated with Visiobond, Scotchbond II, and Ketac Varnish. In addition, five specimens of Variglass were similarly prepared and remained uncoated as per the manufacturer's instructions. F release was measured each day during week 1 and on the last day of weeks 2, 3, and 4. The results indicated that the application of the surface coatings did not completely inhibit F release from glass-ionomer cements, and that F release during the first week for all groups was significantly greater than in the subsequent 3 weeks. Visiobond-coated glass-ionomer cement allowed significantly more F release than Scotchbond II-coated glass-ionomer cement, Ketac Varnish-coated glass-ionomer cement, or Variglass.