1 Department of Orthodontics, University of Homburg, Saar, Germany; Institute of Odontology, Sahlgrenska Academy, University of Gothenburg, Sweden; Private Practice of Orthodontics in Traben-Trarbach, Germany. bludwig@kieferorthopaedie-mosel.de.
2 Private Practice of Orthodontics, Smile Innovation Orthodontics, Tokyo.
3 Department of Orthodontics, University of Münster, Münster, Germany.
4 Department of Orthodontics, University Medical Center of Johannes Gutenberg University Mainz, Mainz, Germany.
5 University of Connecticut School of Dental Medicine, Farmington, CT.