1. 1 School of Health and Life Sciences, Pontifical University Catholic of Rio Grande do Sul, Porto Alegre, Brazil.
2. 2 Department of Restorative Sciences, University of Alabama at Birmingham, School of Dentistry, Birmingham, AL, USA.
3. 3 Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA.
4. 4 Postgraduate Program in Implantology and Periodontology, IOA, Porto Alegre, Brazil.
5. 5 Private practice, Porto Alegre, Brazil.
6. 6 Department of Oral Pathology, Medicine, and Radiology, Indiana University, School of Dentistry, Indianapolis, IN, USA.
7. 7 Department of General Practice, Virginia Commonwealth University, School of Dentistry, Richmond, VA, USA.