All samples showed remaining dentin layer between restoration and pulp, except one sample of DMADDM+NACP at 8 d which had pulp perforation: (A) lower, (B) medium and (C) higher magnification. With pulp exposure, some restorative materials and dentin pieces were pushed into pulp chamber. Nonetheless, there was mild pulpal response similar to other samples without pulp perforation, indicating that the new antibacterial and remineralizing nanocomposite and bonding agent were biocompatible.