[1] Malmo Univ, Fac Odontol, Dept Prosthodont, Malmo, Sweden
[2] Univ Fed Minas Gerais, Dept Community & Prevent Dent, Belo Horizonte, MG, Brazil
[3] Queen Alexandra Hosp, Dept Oral & Maxillofacial Surg, Portsmouth, Hants, England
[4] Univ Fed Minas Gerais, Sch Dent, Dept Oral Surg & Pathol, Belo Horizonte, MG, Brazil