Evaluation of different monomer compositions in polymer-infiltrated lithium disilicate (Li₂Si₂O₅) glass-ceramic

This study aimed to fabricate hybrid blocks by infiltrating various resin compositions into pre-sintered porous lithium disilicate (Li₂Si₂O₅) scaffolds and to evaluate their surface characteristics, mechanical properties, and cytocompatibility. Hybrid ceramic-polymer blocks were produced using mixtures of Bis-GMA, UDMA, and TEGDMA monomers, polymerized at 300 MPa and 180 °C. Four groups (BT82, BT55, UT55, UT73) with different monomer ratios were tested. Complete resin infiltration was achieved in all groups. Surface roughness, contact angle, and water sorption showed no significant differences. However, mechanical properties varied depending on resin composition. UDMA-containing groups (UT55, UT73) exhibited higher flexural strength and Vickers hardness, while Bis-GMA-containing groups showed lower values. Flexural strength was maintained after thermal cycling, but hardness decreased in all groups. All formulations demonstrated excellent cytocompatibility. These results demonstrate that optimizing the resin composition enables the fabrication of lithium disilicate-based hybrid blocks with excellent mechanical properties and biocompatibility, suggesting their potential application as chairside Computer Aided Design/Computer Aided Manufacturing dental restorative materials.