1. Department of Social Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
2. Zilveren Kruis Achmea, Leusden, The Netherlands
3. KNMT, Royal Dutch Dental Association, Utrecht, The Netherlands
4. College of Oral Science, Department of Quality and Safety of Oral Health Care, Radboud University Medical Center, Nijmegen, The Netherlands
5. State Key Laboratory of Oral Disease, West China Hospital of Stomatology, Sichuan University, Chengdu, China
6. Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China