1. Department of Surgery, Faculty of Medicine, Dental Clinic, University of Salamanca, Campus Miguel de Unamuno, 37007 Salamanca, Spain
2. Faculty of Dental Medicine, Universidade Católica Portuguesa, 3504-505 Viseu, Portugal
3. Centre for Interdisciplinary Research in Health (CIIS), Universidade Católica Portuguesa, 3504-505 Viseu, Portugal
4. Department of Prosthesis, Faculty of Health Sciences, Alfonso X El Sabio University, 28691 Madrid, Spain