Polymer characteristics and mechanical properties of bulk-fill, giomer, fiber-reinforced and low-shrinkage composites

Introduction/Objective. The objective was to determine the degree of conversion (DC), cross-link density, percentage leachable monomers, flexural strength (FS), and hardness (HV) nanohybrid, nanofilled bulk-fill, giomer, fiber-reinforced, low-shrinkage composites. Methods. Standardized specimens (n = 5/group) Tetric EvoCeram Bulk Fill, Filtek Beautifil, EverX posterior, Kalore, Z250 (microhybrid control), (nanohybrid control) were subjected micro-Raman spectroscopy, three-point bending, HV. Cross-linking density monomers ascertained based on ratio HV DC before after immersion in absolute ethanol. Results. range 50.4?70.5%, highest for lowest Kalore. %DC change Beautifil (10.3%) (1.4%) (1.28%). FS ranged between 78.9 MPa (TEC) 126.7 (Filtek Bulk). 58.6 (Kalore) 113.9 (Z250) significantly decreased post-immersion (19?55%). HV48h inversely correlated HV% loss (r -0.761), whilst positively with 0.893). Conclusion. Bulk, EverX, showed DC. mechanical properties observed greatest shown by Bulk. There up 10% monomers. correlated.