Comparative assessment of microleakage, resin tag formation, and shear bond strength of an Alkasite and high-viscosity glass-ionomer cements in vitro performances of alkasites and HVGICs

The aim of this study was to evaluate the shear bond strength (SBS), microleakage (ML), and resin tag length (RTL) of three restorative materials—Harvard POWERmer Bulk OptiCaps ® (PB), Fuji IX GP ® FAST (FF), and Cention ® Forte (Alkasite, CF) —when bonded to dentin. Thirty-three occlusal dentin surfaces were prepared and randomly allocated to three groups ( n = 11) for evaluation of shear bond strength. Class V cavities were prepared on the buccal surfaces of 30 third molars and randomly assigned to three groups ( n = 10) for microleakage evaluation. The cavities were restored with Harvard POWERmer Bulk OptiCaps ® (PB), Fuji IX GP ® FAST (FF), or Cention ® Forte (CF). Microleakage was evaluated after immersion in a 1% methylene blue solution for 24 h. Four specimens from each group were randomly selected for scanning electron microscopy to evaluate resin tag formation and length. The data were analyzed using Cohen’s kappa coefficient, the Kruskal–Wallis test, and the Fisher–Freeman–Halton exact test, with the significance level set at α = 0.05. CF exhibited significantly lower microleakage values than FF ( p = 0.028) and PB ( p = 0.001), whereas no significant difference was observed between FF and PB ( p = 0.349). Similarly, CF exhibited significantly higher SBS values than FF ( p = 0.002) and PB ( p < 0.001), whereas no significant difference was observed between FF and PB ( p = 0.579). Alkasite (CF) demonstrated significantly higher SBS than the other groups, and lower microleakage values. Resin tag formation was exclusively observed in the alkasite group. This study evaluated the bonding properties, microleakage, and resin tag formation of an alkasite restorative material in comparison with high-viscosity glass ionomer cements (HVGICs). Evidence regarding these materials, particularly Harvard POWERmer Bulk, remains limited. The findings may contribute to the current body of evidence and provide useful information for clinicians when selecting restorative materials.