Dental Resin Composites Reinforced by Rough Core-Shell SiO 2 Nanoparticles with a Controllable Mesoporous Structure.

A porous structure within filler particles may improve interfacial bonding between the resin matrix and fillers for the preparation of dental resin composites (DRCs). In this study, rough core-shell SiO 2 (rSiO 2 ) nanoparticles with controllable mesoporous structures were synthesized via an oil-water biphase reaction system and characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and N 2 adsorption-desorption measurements. The influence of the mesoporous shell thickness of rSiO 2 and mass ratio between rSiO 2 and smooth SiO 2 (sSiO 2 ) on the physical and mechanical properties of DRCs was studied. The rSiO 2 with a thin mesoporous shell could form a strong physical interlocking with the resin matrix, which improved the mechanical properties with the exception of flexural modulus. The mechanical properties were further optimized by mixing rSiO 2 and sSiO 2 . The flexural strength and compressive strength of the DRC at a mass ratio of 5:5 increased by 24.3% and 16.8%, respectively, compared with the DRC filled with sSiO 2 alone. There is no statistically significant difference in the flexural modulus between these two DRCs ( p > 0.05). The DRCs in this study showed excellent biocompatibility on the human dental pulp cells (HDPCs) as demonstrated by the cytotoxicity tests. The use of rSiO 2 provides a promising approach to develop strong, durable, and biocompatible DRCs.