Self-rated oral health and oral health-related factors: the role of social inequality

Background: The reasons why social inequality is associated with oral health outcomes is poorly understood. This study investigated whether stratification by different measures of socio-economic status (SES) helped elucidate these associations. Methods: Cross-sectional survey data were used from Australia's 2004-06 National Survey of Adult Oral Health. The outcome variable was poor self-rated oral health. Explanatory variables comprised five domains: demographic, economic, general health behaviour, oral health-related quality of life and perceived need for dental care. These explanatory variables were each stratified by three measures of SES: education, income and occupation. Results: The overall proportion of adults reporting fair or poor oral health was 17.0% (95% CI 16.1, 18.0). Of these, a higher proportion were older, Indigenous, non-Australian born, poorly educated, annual income <$20 000, unemployed, eligible for public dental care, smoked tobacco, avoided food in the last 12 months, experienced discomfort with their dental appearance, experienced toothache or reported a need for dental care. In stratified analyses, a greater number of differences persisted in the oral health impairment and perceived need for dental care domains. Conclusions: Irrespective of the SES measure used, more associations between self-rated oral health and dental-specific factors were observed than associations between self-rated oral health and general factors.