[1] Univ Kebangsaan Malaysia, Fac Dent, Dept Restorat Dent, Unit Periodontol, Jalan Raja Muda Abdul Aziz, Kuala Lumpur 50300, Malaysia
[2] Fac Dent Univ Teknol MARA, Ctr Periodontol Studies, Sungai Buloh 47000, Selangor, Malaysia
[3] Univ Kebangsaan Malaysia, Fac Dent, Dept Family Oral Hlth, Jalan Raja Muda Abdul Aziz, Kuala Lumpur 50300, Malaysia
[4] Univ Teknol MARA, Ctr Oral & Maxillofacial Diagnost & Med Studies, Fac Dent, Sungai Buloh 47000, Selangor, Malaysia
[5] Univ Teknol MARA, Inst Pathol, Lab & Forens Med I PPerForM, Sungai Buloh 47000, Selangor, Malaysia