This study will be conducted in two stages. The first stage includes a baseline cross-sectional investigation. Oral health literacy level will be assessed by conducting a structured interview. Background variables, attitude, socioeconomic factors and psychological factors shall be assessed using self-administered questionnaires. A clinical examination will be conducted including general health information and extended oral health examination. The oral health examination performed includes record of oral hygiene status such as dental caries and periodontal status. An assessment of oral bacteria will also be performed.