1. Department of Oral Pathology, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand
2. Department of Stomatology, Faculty of Dentistry, Prince of Songkla University, Hatyai, Songkhla, Thailand
3. Department of Oral Diagnosis, Faculty of Dentistry, Khon Kaen University, Khon Kaen, Thailand
4. Department of Oral Biology and Oral Diagnostic Sciences, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand