1. *Adil Nalçaci, DDS, PhD, research assistant, Department of Restorative Dentistry, Faculty of Dentistry, Ankara University, Ankara, Turkey
2. Nuran Ulusoy, DDS, PhD, professor and chair, Department of Restorative Dentistry, Faculty of Dentistry, Ankara University, Ankara, Turkey
3. Orhan Atakol, professor, Department of Chemistry, Faculty of Science, Ankara University, Ankara, Turkey