Microleakage in Class I Resin Composite Restorations Lined with Glass Ionomer as Dentin Substitute : an In-vitro Study

The purpose of this in vitro study was to compare the microleakage of occlusal resin composite and three glass ionomer/ resin composite techniques. Class I occlusal preparations were initiated on forty molar teeth. Teeth were randomly assigned to four groups of ten. Groups were restored as follow: 1) Solo Plus / Point 4 resin composite, 2) Fuji IX/ Fuji Bond LC/ Point 4, 3) Fuji IX/ Experimental LiquidLiquid glass ionomer bonding material! Point 4, 4) Fuji IX/ Solo Plus / Point 4. After 24 hours storage in distilled water at 37°C, the restoration was subjected to 2500 thermal cycles between 8°C and 48°C with a 30 second dwell time and 10-second transit time. They were placed in a 5% aqueous solution of methylene blue dye for 18 hours. Then, the teeth were sectioned bucco-lingually for microleakage assessment. Results were analyzed using a KruskalWallis One-way ANOVA and Tukey All Pairwise Multiple Comparison procedures. Results showed the glass ionomer/ resin composite treatment groups lined with an experimental liquid-liquid glass ionomer showed significantly less leakage than the resin composite group at p<0.05. There was not a statistical difference between any other groups. It is concluded that using a high strength glass ionomer as a dentin substitute enhances resistance to microleakage when compared to an adhesive resin composite resin.