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Oral health inequality in Canada, the United States and United Kingdom

Research output: Contribution to journalArticlepeer-review

Malini Chari, Vahid Ravaghi, Wael Sabbah, Noha Gomaa, Sonica Singhal, Carlos Quiñonez

Original languageEnglish
Article numbere0268006
Pages (from-to)e0268006
JournalPLoS ONE
Issue number5 May
PublishedMay 2022

Bibliographical note

Funding Information: This research was supported through the generous funding of the Canadian Dental Protective Association and Green Shield Canada. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Publisher Copyright: © 2022 Chari et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

King's Authors


The objective of this study was to quantify the magnitude of absolute and relative oral health inequality in countries with similar socio-political environments, but differing oral health care systems such as Canada, the United States (US), and the United Kingdom (UK), in the first decade of the new millennium. Clinical oral health data were obtained from the Canadian Health Measures Survey 2007-2009, the National Health and Nutrition Examination Survey 2007-2008, and the Adult Dental Health Survey 2009, for Canada, the US and UK, respectively. The slope index of inequality (SII) and relative index of inequality (RII) were used to quantify absolute and relative inequality, respectively. There was significant oral health inequality in all three countries. Among dentate individuals, inequality in untreated decay was highest among Americans (SII:28.2; RII:4.7), followed by Canada (SII:21.0; RII:3.09) and lowest in the UK (SII:15.8; RII:1.75). Inequality for filled teeth was negligible in all three countries. For edentulism, inequality was highest in Canada (SII: 30.3; RII: 13.2), followed by the UK (SII: 10.2; RII: 11.5) and lowest in the US (SII: 10.3; and RII: 9.26). Lower oral health inequality in the UK speaks to the more equitable nature of its oral health care system, while a highly privatized dental care environment in Canada and the US may explain the higher inequality in these countries. However, despite an almost equal utilization of restorative dental care, there remained a higher concentration of unmet needs among the poor in all three countries.

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