Effect of glass ionomer manipulation on early fluoride release

Abstract

Purpose: To determine the amount of fluoride released from several glass ionomer products [Fuji Cap II, Fuji Ionomer Type II, Ketac-Silver, Chelon-Silver, and Miracle Mix (hand-mixed and encapsulated)], and to compare them between triturated (5, 10, 15 seconds) encapsulated and hand-mixed glass ionomers.

Materials and methods: The amount of fluoride released at 1, 2, 3, 7, 14, 21 and 28 days after the start of immersion in deionized-distilled water at 37 degrees C was determined with a fluoride ion selective electrode. Rates of fluoride release and cumulative amounts of fluoride release were calculated.

Results: Each glass ionomer released the greatest amount of fluoride during the first 24-hour period. Although there was some variation between products, generally the hand-mixed specimens released significantly (P < 0.05) less fluoride than those prepared by mechanical trituration (10 and 15 seconds). The cumulative amounts of fluoride released from the mechanically triturated glass ionomers were significantly (P < 0.05) greater than the amounts released from the hand-mixed glass ionomers. No significant differences in the cumulative amounts of fluoride released from triturated materials were found among the different trituration times.