1. Division of Periodontology and Implant dentistry Faculty of Dentistry The University of Hong Kong Hong Kong China
2. European Research Group on Periodontology (ERGOPerio) Genova Italy
3. Department of Oral and Maxillo‐facial Implantology Shanghai Key Laboratory of Stomatology National Clinical Research Centre for Stomatology Shanghai Ninth People Hospital School of Medicine Shanghai Jiao Tong University Shanghai China