1. Department of Periodontology, School of Dentistry, Tri-Service General Hospital and National Defense Medical Center, Taipei 11490, Taiwan
2. Department of Dentistry, Wan Fang Hospital, Taipei Medical University, Taipei 11696, Taiwan
3. Graduate Institute of Injury Prevention and Control, College of Public Health, Taipei Medical University, Taipei 11031, Taiwan
4. School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 11031, Taiwan