1. Post Graduate Program in Dental Science; Federal University of Santa Maria; Rua Marechal Floriano Peixoto, 1184 Santa Maria RS 97015-270 Brazil
2. Department of Restorative Dentistry; Federal University of Santa Maria; Rua Marechal Floriano Peixoto, 1184 Santa Maria RS 97015-270 Brazil
3. Department of Stomatology; Federal University of Santa Maria; Rua Marechal Floriano Peixoto, 1184 Santa Maria RS 97015-270 Brazil