title: Impact of national income and inequality on sugar and caries relationship.
abstract: OBJECTIVE
  The aim of this study was to examine the impact that national income and income inequality in high and low income countries have on the relationship between dental caries and sugar consumption.
  
  
  METHODS
  An ecological study design was used in this study of 73 countries. The mean decayed, missing, or filled permanent teeth (DMFT) for 12-year-old children were obtained from the WHO Oral Health Country/Area Profile Programme. United Nations Food and Agricultural Organization data were used for per capita sugar consumption. Gross national incomes per capita based on purchasing power parity and the Gini coefficient were obtained from World Bank data. Bivariate and multivariate linear regression analysis was performed to estimate the associations between mean DMFT and per capita sugar consumption in different income and income inequality countries.
  
  
  RESULTS
  Bivariate and multivariate regression analysis showed that countries with a high national income and low income inequality have a strong negative association between sugar consumption and caries (B = -2.80, R2 = 0.17), whereas countries with a low income and high income inequality have a strong positive relationship between DMFT and per capita sugar consumption (B = -0.89, R2 = 0.20).
  
  
  CONCLUSIONS
  The relationship between per capita consumption of sugar and dental caries is modified by the absolute level of income of the country, but not by the level of income inequality within a country.
authors.affiliation: Center of Studies for Community Dentistry, Faculty of Dentistry, Universiti Teknologi MARA, Shah Alam, Malaysia. drmasoodmohd@gmail.com
authors.forename: M
authors.initials: M
authors.lastname: Masood
authors.forename: Y
authors.initials: Y
authors.lastname: Masood
authors.forename: T
authors.initials: T
authors.lastname: Newton
mesh_terms: D002648:Child; D004245:DMF Index; D003731:Dental Caries / Q000453:epidemiology* / Q000209:etiology; D019049:Developed Countries / Q000191:economics; D003906:Developing Countries / Q000191:economics*; D019422:Dietary Sucrose / Q000009:adverse effects / Q000600:supply & distribution*; D059066:Gross Domestic Product; D054624:Health Status Disparities; D006801:Humans; D007182:Income; D016014:Linear Models; D018803:Models, Economic
chemical_list: D019422:Dietary Sucrose