1. Department of Surgical, Medical, Molecular and Critical Area Pathology, Unit of Pediatric Dentistry, University of Pisa, Via Roma 67, 56126 Pisa, Italy
2. Department of Life, Health and Environmental Sciences, University of L’Aquila, Coppito Piazzale Salvatore Tommasi 1, 67100 L’Aquila, Italy
3. University Vita-Salute San Raffaele, Dental Clinic, Via Olgettina 60, 20132 Milano, Italy