Athanasios Athanasiou, DDS, MSD, PhD Professor, Chairman and Program Director at the Department of Orthodontics, School of Dentistry, Aristotle University of Thessaloniki, Greece. He has published more than 140 scientific articles, chapters and books, has supervised 45 Ph.D. and Master theses, and he has presented more than 345 lectures, papers and seminars in 46 countries.