1. Oral and Dental Health Department, Altınbaş University, 34147 İstanbul, Turkey
2. Department of Periodontology, Institute of Dentistry, University of Turku, 20520 Turku, Finland
3. Radiation Oncology Department, Başakşehir Çam and Sakura City Hospital, 34380 İstanbul, Turkey
4. Department of Oral and Maxillofacial Diseases, Helsinki University Hospital, University of Helsinki, 00290 Helsinki, Finland
5. Section of Periodontology and Dental Prevention, Division of Oral Diseases, Department of Dental Medicine, Karolinska Institutet, 17176 Stockholm, Sweden