1. Dental Research Center, Department of Oral Medicine, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran.
2. Department of Oral Medicine, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran.
3. Department of Oral and Maxillofacial Surgery, School of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran.
4. Research Center for Health Sciences and Department of Epidemiology & Biostatistics, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran.