Dental materials have been utilized in most of the branches of dentistry including restorative dentistry. Glass Ionomer Cement (GIC) is one of the most popular restorative materials in dentistry and have been applied in numerous clinical applications. Despite that, conventional GIC is physically and mechanically weak. Consequently, the composition of GIC have been formulated and modified to overcome these limitations. One of the way to enhance the performance of GIC is by adding inorganic fillers into the material. Nano-fillers have been added into conventional GIC and demonstrated a better performance in terms of its physical and mechanical properties. We present this special book to provide information on GIC, specifically highlighting the addition of nano-hydroxyapatite-silica and its effects on the material’s performance. Additionally, this book explores various methods for incorporating nanotechnology in dental materials. We hope it offers valuable insights regarding this innovative material, which has the potential to serve as an alternative in restorative dentistry.