1. Assistant Professor, Dental and Periodontal Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
2. Associate Professor, Department of Endodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran
3. Professor of Endodontics, Dental and Periodontal Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
4. Associate Professor of Biostatistics, Department of Statistics and Epidemiology, Faculty of Health, Tabriz University of Medical Sciences, Tabriz, Iran