1. Department of Medical-Surgical Specialties, Section of Orthodontics, School of Dentistry, University of Catania, Policlinico Universitario V. Emanuele, Catania, Italy
2. Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Section of Orthodontics, School of Dentistry, University of Messina, Policlinico Universitario G. Martino, Messina, Italy