1. Department of Community and Preventive Dentistry; School of Dentistry; Federal University of Minas Gerais; Belo Horizonte Brazil
2. School of Dentistry; Federal University of Minas Gerais; Belo Horizonte Brazil
3. Hospital Fundation of Minas Gerais State; Betim Brazil
4. Estadual University of Montes Claros; Montes Claros Brazil