Biocompatibility is an essential criteria for a dental material as to ensure safety for the patients before it is placed into the oral cavity. Glass Ionomer Cement (GIC) is one of the most biocompatible dental restorative material and it has been used widely in clinical application. Nevertheless, conventional GIC has some drawbacks such as poor physical and mechanical properties hence lead to the development of nano-hydroxyapatite-silica (nano-HA-silica) fillers. These filler is added to conventional GIC to increase the material’s strength and it has undergone some evaluation in terms of its properties. We introduce this special book to give information regarding this novel material and discuss about its cytotoxicity, cell attachment and dentinogenic differention properties in response to Dental Pulp Stem Cells and selected odontogenic gene markers. It is hope that this book will provide new insight about this novel material which has the potential to be an alternative material for use in restorative dentistry.