A new photocurable composite resin for dental restorations was synthesized using a monovinyl acrylate diluent. Its polymerization shrinkage, shrinkage stress, degree of conversion, and mechanical properties were investigated and compared to those of a conventional composite resin synthesized using a triethyleneglycol dimethacrylate diluent as well as three commercial resins: Tetric N-Ceram, Neofil, and Gradia Direct. The polymerization shrinkage and shrinkage stress of the new composite resin were statistically lower than those of the conventional resin (p0.05). The degree of conversion of the new resin was statistically better than all other tested resins (p0.05). The mechanical properties of the resins were not statistically different (p>0.05). Overall, the new composite resin exhibited less polymerization shrinkage, lower shrinkage stress, a higher degree of conversion, and similar mechanical properties to the other resins, demonstrating its potential for clinical application.