By Crispian Scully, CBE, MD, PhD, MDS, MRCS, FDSRCS, FDSRCPS, FFDRCSI, FDSRCSE, FRCPath, FmedSci, FHEA, DSc, Dean and Director of Studies and Research, and Professor of Oral Medicine, Pathology and Microbiology, University of London, London, UK; Eastman Dental Institute, and WHO Collaborating Centre for Disability, Culture and Oral Health, University College London, UK; Visiting Professor at Universities of Edinburgh, Helsinki, Middlesex and West of England; Honorary Consultant at University College Hospitals, London, UK; Great Ormond Street Hospital, London; John Radcliffe Hospital, Oxford, UK; and European Institute for Oncology, Milan, Italy |