1. Graduate Orthodontic Program, Department of Experimental and Clinical Medicine The University of Florence Florence Italy
2. Department of Experimental and Clinical Medicine The University of Florence Florence Italy
3. Graduate Program in Orthodontics, Department of Dentistry Pontifical Catholic University of Minas Gerais Belo Horizonte Brazil
4. Thomas M. Graber Visiting Scholar, Department of Orthodontics and Pediatric Dentistry, School of Dentistry The University of Michigan Ann Arbor Michigan USA