To protect glass-ionomer cement from moisture contamination and dehydr
ation during initial setting, immediate application of a surface coati
ng agent is recommended. This study compared the effect of various sur
face coatings on F release from glass-ionomer cement. Twenty glass-ion
omer cement (Ketac-Fil Aplicap) disks (4.52 cm2) were prepared from a
Teflon mold. The control group was uncoated, while the experimental gr
oups were coated with Visiobond, Scotchbond II, and Ketac Varnish. In
addition, five specimens of Variglass were similarly prepared and rema
ined uncoated as per the manufacturer's instructions. F release was me
asured 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 d
id not completely inhibit F release from glass-ionomer cements, and th
at F release during the first week for all groups was significantly gr
eater than in the subsequent 3 weeks. Visiobond-coated glass-ionomer c
ement allowed significantly more F release than Scotchbond II-coated g
lass-ionomer cement, Ketac Varnish-coated glass-ionomer cement, or Var
iglass.