The magnitude of Indigenous and non-Indigenous oral health inequalities in Brazil, New Zealand and Australia

Objective: To compare the magnitude of relative oral health inequalities between Indigenous and non-Indigenous persons from Brazil, New Zealand and Australia. Methods: Data were from surveys in Brazil (2010), New Zealand (2009) and Australia (2004-06 and 2012). Participants were aged 35-44 years and 65-74 years. Indigenous and non-Indigenous inequalities were estimated by prevalence ratios (PR) and their corresponding 95% confidence intervals (CI), adjusting for sex, age and income. Outcomes included inadequate dentition, untreated dental caries, periodontal disease and the prevalence of "fair" or "poor" self-rated oral health in Australia and New Zealand, and satisfaction with mouth/teeth in Brazil (SROH). Results: Irrespective of country, Indigenous persons had worse oral health than their non-Indigenous counterparts in all indicators. The magnitude of these ratios was greatest among Indigenous and non-Indigenous Australians, who, after adjustments, had 2.77 times the prevalence of untreated dental caries (95% CI 1.76, 4.37), 5.14 times the prevalence of fair/poor SROH (95% CI 2.53, 10.43). Conclusion: Indigenous people had poorer oral health than their non-Indigenous counterparts, regardless of setting. The magnitude of the relative inequalities was greatest among Indigenous Australians for untreated dental decay and poor SROH.