Microleakage of an Enhanced Resin-Modified Glass Ionomer Restorative Material in Primary Molars

Resin composites, glass ionomers (GIs), or a combination of these materials have gradually replaced silver amalgam in pediatric dentistry. The purpose of this study was to compare the microleakage of Class II (box only) cavity restorations with ACTIVA Bioactive Restorative Glass, resin-modified GI (RMGI), and composite in primary molars. A total of 65 primary molars with at least one intact proximal surface were selected in this in-vitro study. After debridement of each tooth, Class II (box only) cavities were prepared. Based on the type of the restorative material and the application of etching and bonding adhesives, the samples were categorized into five groups: (1) composite; (2) RMGI (Fuji II LC)+conditioner; (3) RMGI (Fuji II LC); (4) enhanced RMGI (ACTIVA Bioactive Restorative Glass)+etching/bonding; and (5) ACTIVA Bioactive Restorative Glass. The restored teeth were thermocycled for 2000 cycles. After embedding in an acrylic resin, the degree of dye penetration at axial and gingival walls was assessed using a stereomicroscope. The data were statistically analyzed by analysis of variance (ANOVA) and Tukey's test. Resin-based composite (RBC) Z250 showed the least microleakage, while RMGI showed maximum microleakage at axial walls. The mean degree of microleakage at gingival margins was the lowest in RBC Z250 and ACTIVA+etching/bonding groups and the highest in RMGI+conditioner and RMGI groups. The microleakage of ACTIVA Bioactive Restorative material in the absence or presence of etching and bonding could be comparable to the microleakage of composites.