1. Department of Dentistry, Vita Salute University, San Raffaele Hospital, Milan, Italy
2. Private practitioner, Sammarate, Varese, Italy
3. Private practitioner, Roma, Italy
4. Department of Biomedical Sciences, CNR Institute of Neurosciences University of Padova, Padova, Italy
5. Dental School, University G. d'Annunzio, Chieti-Pescara, Chieti, Italy