1. Conservative Dentistry, Faculty of Dentistry, University of Hong
Kong, Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong, SAR, China;
2. Bauru School of Dentistry, University of São Paulo, Brazil;
3. Department of Dental Materials, University of Granada, Spain; and
4. Department of Oral Biology and Maxillofacial Pathology, School of
Dentistry, Medical College of Georgia, Augusta, GA, USA;