Evaluation of Silica and Bioglass Nanomaterials in Pulp-Like Living Materials

Although silicon is a widespread constituent in dental materials, its possible influence on teeth formation and repair remains largely unexplored. Here we have studied the effect of two silicic acid-releasing nanomaterials, silica and bioglass, on a living model of pulp consisting of dental pulp stem cells seeded in dense type I collagen hydrogels. Silica nanoparticles and released silicic acid had little effect on cell viability and mineralization efficiency but impacted metabolic activity, delayed matrix remodeling and led to heterogeneous cell distribution. Bioglass improved cell metabolic activity and led to a homogenous dispersion of cells and mineral deposits within the scaffold. These results suggest that the presence of calcium ions in bioglass is not only favorable to cell proliferation but can also counter-balance the negative effects of silica and silicic acid. Both chemical and biological processes should therefore be considered when investigating the effect of silicon-containing materials on dental tissues.