1. Department of Endodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
2. Dental Student's Scientific Research Center (DSSRC), School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
3. Laser Research Center in Dentistry (LRCD), School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
4. Iranian Center for Endodontic Research, Research Institute of Dental Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.