doi:10.1038/nindia.2017.23 Published online 16 March 2017
• Improve the environment through water fluoridation, smoke-free legislation, and higher tobacco taxes.
• School-based programmes including fluoride application.
• Multiple policies aimed at reducing sugar consumption.
• Policies to encourage healthier products on the market.
• Incorporating dental treatment into a universal healthcare insurance system.
Oral diseases are the most prevalent diseases worldwide1, and their estimated annual treatment cost is US$298 billion2. The resulting absenteeism from education and work increases the annual indirect cost of oral diseases to US$144 billion, comparable to the annual indirect cost of US$126 billion for lower respiratory infections, one of the 10 most frequent global causes of death2.
There is a relationship between oral diseases and socioeconomic status called a social gradient of oral health; poor people have more oral diseases and rich people have healthier teeth and gums3. These inequalities are observed between and within countries, and cannot be solely explained by inequalities in dental care provision. The global burden of oral diseases is different because of health inequalities; therefore, reducing oral health inequalities is important to reduce the burden3.
Figure 1 shows the oral health inequalities (social gradient) and effects of different types of interventions. Studies reveal that human behavior and health are affected by various social circumstances; so approaches based on changing the environment are effective in preventing diseases and reducing oral health inequalities. Approaches relying on individual efforts do not improve the health of the disadvantaged population and sometimes increase health inequalities. Because there are inequalities in both the incidence and treatment of diseases, focusing only on treatment will not eliminate health inequalities.
Moreover, most oral diseases are preventable, and prevention is more cost-effective than treatment. Water fluoridation (changing the fluoride concentration of drinking water to 1 mg/L (similar to fluoride concentration in tea) is a notable example of a preventive public health policy to reduce health inequalities. This policy is effective regardless of socioeconomic status. Because of the lack of preventive dental behavior among poorer people, fluoridation of drinking water is more beneficial to them. Water fluoridation is established in several Asia-Pacific countries and has successfully reduced tooth decay and its inequalities4. Other policy-based approaches include legislation for smoke-free spaces and the raising of tobacco taxes, which would change the air quality of workplaces, restaurants, and/or bars, and therefore would change smoking habits and tobacco-related diseases and death5, 6. As smoking is a major risk factor for oral cancer and periodontal disease, tobacco control policies would reduce oral health inequalities.
Implementing policies to build an oral-health positive environment in school may also benefit children, regardless of the socioeconomic circumstances of their families. The Fit for School programme in the Philippines includes offering evidence-based general and oral health interventions such as fluoride toothpaste for brushing to students of public elementary schools7. These cost-effective and sustainable interventions successfully reduce oral diseases7. In Japan, the school-based fluoride mouthrinse programme is conducted in several areas and has reduced decay and its geographical inequalities8. Pit and fissure sealant programmes at school may also reduce caries inequalities. Because good health during childhood is crucial later in life, school-based health promotion is an important policy option,
Private companies and government support
Input by private companies and government regulation for these companies are also essential to change the environment. For example, fluoride toothpaste is an important preventer of caries in developed countries, and the efforts of private companies to include fluoride into their dentifrices have played a role in diffusing fluoride dentifrice into market. In countries where most of the toothpastes contain fluoride, people easily benefit by using it.
Reducing sugar consumption is a key public health agenda, especially for obesity and caries prevention. Nutrition labeling, regulation of marketing for sugary food and drinks, and policies promoting sugar-free products, are among measures in World Health Organization guidelines9. To implement these measures, cooperation of the government and the private sector is necessary. Higher sugar consumption in developed countries and increasing sugar consumption in developing countries are a threat to health. However, sugar consumption in Japan is an exception; per capita sugar consumption in Japan had been falling since the 1970s and reached 16.7 kg/person/year, which was lower than that in Australia (47.3 kg/person/year) and India (20.0 kg/person/year), in 2012–1410. Increasing the choice of sugar-free drinks and low sugar food products in the market would contribute to reduced sugar consumption. The availability of sugar-free medicine for children with chronic diseases could reduce their risk of decay. To promote healthier products in the market, evidence-based policy implementation is necessary.
These measures are related to prevention of oral diseases; but, once disease occurs, dental treatment is necessary. A universal healthcare insurance system reduces the economic burden on patients. Incorporating dental treatment into a universal healthcare insurance system is desirable for reducing oral health inequalities. In conclusion, reducing oral health inequalities in Asia-Pacific countries require multiple policy-based approaches to build an environment that makes healthy choices easier, regardless of the socioeconomic circumstances.
1Associate Professor, Department of International and Community Oral Health, Tohoku University Graduate School of Dentistry, Japan (firstname.lastname@example.org).
2. Listl, S. et al. Global economic impact of dental diseases. J. Dent. Res. 94, 1355-1361 (2015)
3. Watt, R. et al (eds.). Social inequalities in oral health: from evidence to action. London: UCL Research Department of Epidemiology and Public Health (2015)
4. Cho, H. J. et al. Association of dental caries with socioeconomic status in relation to different water fluoridation levels. Community Dent. Oral Epidemiol. 42, 536–542 (2014)
5. Song, A. V. et al. Association of smoke-free laws with lower percentages of new and current smokers among adolescents and young adults: An 11-year longitudinal study. J. Am. Med. Assoc. Pediatrics 169, e152285 (2015)
6. Levy, D. T. et al. Smoking-related deaths averted due to three years of policy progress. Bull. World Health Organ. 91, 509-518 (2013)
7. Monse, B. et al. The Fit for School Health Outcome Study - a longitudinal survey to assess health impacts of an integrated school health programme in the Philippines. BMC Pub. Health 13, 256 (2013)
8. Matsuyama, Y et al. School-based fluoride mouthrinse program dissemination associated with decreasing dental caries inequalities between Japanese prefectures: an ecological study. J. Epidemiol. (in press).
9. WHO: Guideline: Sugars intake for adults and children. Geneva: World Health Organization (2015)
10. OECD and FAO: A.12.2 Sugar projections: Consumption, per capita. In: OECD-FAO Agricultural Outlook 2015. Paris: OECD Publishing (2015)