1. Department of Geriatric Dentistry Peking University School and Hospital of Stomatology Beijing People's Republic of China
2. Department of Oral Implantology, Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Provincial Key Laboratory of Stomatology Sun Yat‐Sen University Guangzhou People's Republic of China
3. Department of Prosthodontics, The First Clinical Division Peking University School and Hospital of Stomatology Beijing People's Republic of China
4. Beijing Institute of Dental Research, Beijing Stomatological Hospital and School of Stomatology Capital Medical University Beijing People's Republic of China