1. * Department of Community Oral Health and Clinical Prevention, Faculty of Dentistry, Universiti Malaya , Kuala Lumpur , Malaysia
2. † Kulliyyah of Dentistry, International Islamic University Malaysia, Kuantan Campus , Pahang , Malaysia
3. ‡ Department of Paediatric Dentistry and Orthodontics, Faculty of Dentistry, Universiti Malaya , Kuala Lumpur , Malaysia
4. § Oral Health Program, Ministry of Health Malaysia, Federal Government Administrative Centre , Putrajaya , Malaysia