Influence of oral health-related behaviours on income inequalities in oral health among adolescents

Objectives: To determine income inequalities in both perceived oral health and oral health-related behaviours and the role oral health-related behaviours in explaining income inequalities in perceived oral health among Sri Lankan adolescents. Methods: The sample included 1218 fifteen-year-olds selected from 48 schools in the Colombo district using a stratified cluster sampling technique. Data were collected by means of questionnaires to both adolescents and their parents. Perceived oral health status was the oral health outcome considered while oral health-related behaviours included brushing frequency, use of dental services in the preceding year and consumption of sugary food/drinks and fruit/vegetables. Results: Tooth brushing frequency, use of dental services in the preceding year and consumption of fruit/vegetables were associated with perceived oral health status. Also, the trends in perceived oral health and all oral health behaviours across ordered income groups were statistically significant. However, it was evident from the Poisson regression models that the effect of income on perceived oral health did not attenuate significantly following adjustment for oral health behaviours. Conclusions: This study demonstrated that oral health behaviours were associated with perceived oral health and also the existence of income gradients in perceived oral health and oral health behaviours. However, oral health behaviours were not accountable for the observed income gradients in perceived oral health.