1. Department of Periodontics and Oral Medicine; University of Michigan School of Dentistry; Ann Arbor MI USA
2. Oral and Maxillofacial Surgeon; CICOM; Center of Implantology; Oral and Maxillofacial Surgery; Badajoz Spain
3. Department of Oral Surgery and Implantology; University of Granada; Granada Spain
4. Department of Mathematics; University of Extremadura; Badajoz Spain