1. Professor and Head of Unit of Prosthodontics, University Dental Hospital of Manchester
2. Consultant/Honorary Senior Lecturer in Restorative Dentistry, Edinburgh Dental Institute
3. Senior Lecturer/Honorary Consultant in Restorative Dentistry, Charles Clifford Dental School, Sheffield, and Anthony Johnson, MMedSci, PhD, Lecturer in Dental Technology, Charles Clifford Dental School, Sheffield.