Dental composite resins are types of synthetic resins which are used in dentistry as restorative material or adhesives. Synthetic resins evolved as restorative materials since they were insoluble, aesthetic, and insensitive to dehydration and were inexpensive. It is easy to manipulate them as well. This book presents current research in the study of dental composites, including dental composites with nano-scaled fillers; the mechanical properties of resin composite core materials; the design and development of novel urethane dimethacrylate monomers in dental compositions; and the development of low-shrinkage dental composites.