1. Division of Geriatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai 50200, Thailand
2. Intercountry Centre for Oral Health, Department of Health, Ministry of Public Health, Chiang Mai 50000, Thailand
3. Department of Mechanical Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai 50200, Thailand
4. Department of Oral Biology and Oral Diagnostic Sciences, Faculty of Dentistry, Chiang Mai University, Chiang Mai 50200, Thailand
5. Department of Prosthodontics, Faculty of Dentistry, Chiang Mai University, Chiang Mai 50200, Thailand