1. Department of PeriodontologyFaculty of DentistryKhon Kaen University Khon Kaen Thailand
2. Chronic Inflammatory Diseases and Systemic Diseases Associated with Oral Health Research GroupKhon Kaen University
3. Department of Obstetrics and Gynecology, Faculty of MedicineKhon Kaen University
4. Dental DivisionKhon Kaen Hospital Khon Kaen Thailand
5. Department of Microbiology and Research Unit on Oral Microbiology and ImmunologyFaculty of Dentistry, Chulalongkorn University Bangkok Thailand
6. Department of EpidemiologyNew York University College of Dentistry New York NY USA
7. Department of Community DentistryFaculty of Dentistry, Khon Kaen University