1. Department of Biomedical and Neuromotor Sciences; University of Bologna; Bologna Italy
2. ARDEC; Ariminum Odontologica; Rimini Italy
3. Faculty of Dentistry; University of Medical Science; La Habana Cuba
4. Unit of Implantology and Prosthodontics; Department of Health Sciences; Dental Clinic; San Paolo Hospital; University of Milan; Milan Italy
5. Center for Dental Medicine; University of Zurich; Zurich Switzerland
6. University of Bern; Bern Switzerland