1 Oncology Unit, Azienda Ospedaliera di Alessandria SS, Antonio e Biagio e Cesare Arrigo, Alessandria I-15121, Italy. Electronic address: vfusco@ospedale.al.it.
2 Sector of Oral Medicine, Department of Surgical, Oncological, and Oral Sciences, Universitè degli Studi di Palermo, Palermo, Italy.
3 Regional Center for Prevention, Diagnosis and Treatment of Medication and Radiation-Related Bone Diseases of the Head and Neck, University of Padua, Padua, Italy.