The Editors Henry F. Duncan BDS, FDS RCS (Ed), MClin Dent, MRD RCS, FFD RCSI, PhD is a Professor and Consultant in Endodontics in the Division of Restorative Dentistry and Periodontology at Dublin Dental University Hospital, Trinity College in Dublin, Ireland Ikhlas A. El-Karim BDS, FDS RCS (Ed), FFD RCSI, PGCHET, PhD is a Clinical Professor and Consultant in Restorative Dentistry in the School of Medicine, Dentistry and Biomedical Sciences at Queen’s University Belfast, Northern Ireland, UK