1. School & Hospital of Stomatology, Wuhan University, Wuhan, China
2. Radboud University Medical Center, Radboud University, Nijmegen, the Netherlands
3. University Medical Center Groningen, University of Groningen, Groningen, the Netherlands;
4. School of Dental Medicine/Medical Faculty, University of Bern, Bern, Switzerland; Universitas Indonesia, Jakarta, Indonesia