1 Department of Orthodontics, University of Homburg, Saar, Germany; Institute of Odontology, Sahlgrenska Academy, University of Gothenburg, Sweden; Private Practice of Orthodontics, Traben-Trarbach in Germany. bludwig@kieferorthopaedie-mosel.de.
2 Private Practice of Orthodontics in Naples and Vicenza, Italy.
3 Department of Dental and Maxillo-Facial Sciences, Section of Orthodontics and Gnathology, University of Naples Federico II, Naples, Italy.
4 Private Practice of Orthodontics in Baku, Azerbaijan.
5 School of Medicine, University of Salerno, Fisciano, Italy; University of Naples Federico II, Naples, Italy.