1. Fabián Murillo-Gómez, DDS, MS, PhD student, Dental Materials Division, Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, São Paulo, Brazil, and Department of Restorative Dentistry, School of Dentistry, University of Costa Rica, San José, Costa Rica
2. Frederick Allen Rueggeberg, DDS, MS, Department of Oral Rehabilitation, Section of Dental Materials, Dental College of Georgia, Augusta University, Augusta, GA, USA
3. Mario Fernando De Goes, DDS, MS, PhD, Dental Materials Division, Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, Piracicaba, São Paulo, Brazil