1. Department of Diagnosis and Surgery, School of Dentistry at Araraquara, UNESP, Araraquara 14801-385, Brazil
2. Department of Periodontology, Tufts University School of Dental Medicine, Boston, MA 02111, USA
3. National Dental Research Institute Singapore, National Dental Centre, Singapore 168938, Singapore
4. Oral Health Academic Clinical Programme, Duke-NUS Medical School, Singapore 169857, Singapore