Inequalities in oral health: Understanding the contributions of education and income.

OBJECTIVE: To quantify the extent to which income and education explain gradients in oral health outcomes.

METHODS: Using data from the Canadian Community Health Survey (CCHS 2003), binary logistic regression models were constructed to examine the relationship between income and education on self-reported oral health (SROH) and chewing difficulties (CD) while controlling for age, sex, ethnicity, employment status and dental insurance coverage. The relative index of inequality (RII) was utilized to quantify the extent to which income and education explain gradients in poor SROH and CD.

RESULTS: Income and education gradients were present for SROH and CD. From fully adjusted models, income inequalities were greater for CD (RIIinc = 2.85) than for SROH (RIIinc = 2.75), with no substantial difference in education inequalities between the two. Income explained 37.4% and 42.4% of the education gradient in SROH and CD respectively, whereas education explained 45.2% and 6.1% of income gradients in SROH and CD respectively. Education appears to play a larger role than income when explaining inequalities in SROH; however, it is the opposite for CD.

CONCLUSION: In this sample of the Canadian adult population, income explained over one third of the education gradient in SROH and CDs, whereas the contribution of education to income gradients varied by choice of self-reported outcome. Results call for stakeholders to improve affordability of dental care in order to reduce inequalities in the Canadian population.