1. Division of Preventive Dentistry, Department of Oral Health Science, Faculty of Dentistry & Graduate School of Medical and Dental Sciences, Niigata University, Niigata City 951-8514, Japan
2. Department of Community Dentistry, Faculty of Dentistry, Mahidol University, 10400 Bangkok, Thailand
3. Centre for Education and Research on Ageing, Concord Repatriation General Hospital, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW 2139, Australia
4. Concord Clinical School, Faculty of Medicine & Health, The University of Sydney, Sydney, NSW 2139, Australia