Fluoride release and uptake abilities of conventonal glass ionomer cements affected by ultrasonic curing.

Objective: the objective of the study was to assess the effect of ultrasonic cur- ing on the fluoride release/uptake ca- pacities of two conventional glass ionomer cements (Fuji II and Fuji IX GP; GC Corporation, Tokyo, Japan). Methods : twenty discs of each materi- al were prepared and stored in deion- ized water at 37 °C. Two different cur- ing methods were investigated: stan- dard conditions and ultrasonic excita- tions. Cumulative fluoride release was meas- ured on days 1, 2, 3, 5, 7, 21, 35, and 49, then fluoride gel was applied to all the groups tested, and fluoride release (after reuptake) was measured on days 56, 70, 84, and 224 using a ion analyzer. Results : no significant differences were found between standard and ultrason- ic curing for Fuji II cement, whereas us- ing the Fuji IX GP cement a remarkable increase of fluoride release was report- ed when ultrasonic curing was per- formed. After exposure to fluoride gel, fluoride release increased significantly for all the groups tested. Significance: Ultrasonic curing does not affect fluoride release of Fuji II, whereas significantly increase fluoride release of Fuji IX GP.