Healthy teeth and gums give us a nice smile, but not everyone can afford them.
Photo: Einar Nilsen
Despite increasing prosperity in Norway over the last century, significant social health inequalities still remain (1) . High earners with a lengthy education live longer and enjoy better health than those with less education and lower incomes. Dental health is a strong indicator of the disparities.
Everyone who has experienced toothache has had an unpleasant reminder of the impact of our teeth and mouths on our mental and physical well-being. Good oral health is essential for core human activities such as eating, talking and socialising with others. It is therefore striking how little attention is paid to oral health in the public discourse – and in global health policy.
Oral diseases are among the most common health problems worldwide and affect over 3.5 billion people (2) . The most common problems are untreated caries, followed by periodontitis, tooth loss and cancer of the lips or oral cavity. The highest numbers of cases are found in low-income countries, where the majority of the population has untreated caries, and dental care is a luxury reserved for the rich and privileged. In low- and middle-income countries, tooth decay is also a major health problem among children, and can cause severe pain and high levels of school absence (3) . In high-income countries, impaired dental health is mainly a problem in the adult and older population.
Despite the causes of dental caries and how it can be prevented being well-documented, the global burden of untreated caries in primary teeth and permanent teeth has changed little in the last 30 years. Radical change has widely been called for in how we think about the prevention and treatment of oral diseases (4) . High-income countries have a strong focus on stimulating health-promoting behaviour among the population and using ever-more advanced technology and methods to repair teeth. This may have overshadowed the need to make changes at a political level and to do something about the two most important drivers of inequality in oral health: the so-called social and commercial determinants.
The latest living conditions survey on health in Norway shows that people with impaired health use more health services. The exception is dental services
The latest living conditions survey on health in Norway shows that people with impaired health use more health services (5) . The exception is dental services. The highest proportion with an unmet need for a dentist is found among the very group that has health problems, not least in relation to mental health: one in four with impaired mental health failed to contact a dentist when they needed dental health care. A clear association has also been found between income, dental health and how often dental care is sought. The low-income group had a higher tendency towards poor dental health than those in higher income brackets. Nevertheless, the former group visits the dentist less often than others, with stretched finances being the most common reason reported (5) .
The Norwegian Act relating to Public Dental Services of 1949 was the starting point for the public dental health service in Norway. One of the aims of the law was to ensure widespread coverage of dentists, including in rural areas. Free school dental care ensured that tooth decay in children and adolescents was largely eradicated. Today, dental health is relatively good at the population level (5) , but some groups tend to fall outside. The Storting's decision in 2018 to review the reimbursement schemes for dental services was an important step in addressing the social inequality in dental health. At a global level, reforms to introduce universal health insurance and integrate dental services with the general health service have yielded good results in several countries (4) .
Poor diet, use of tobacco products and harmful alcohol use are common risk factors for oral and non-communicable diseases (NCDs), including cardiovascular disease, diabetes and cancer (6) . The current high sugar intake levels are of particular concern in relation to the epidemic of caries, obesity and diabetes. In most countries, sugar intake is far higher than the WHO's recommendation for the daily intake of free sugars to be less than 10 % of the total energy intake (7) . One of the reasons for the high sugar intake is the Big Sugar industry. In the global diet, carbonated drinks are a major source of sugar in a market dominated by a few companies, such as the Coca-Cola Company and PepsiCo. These two companies alone account for more than a third of carbonated drink sales worldwide, with total revenues of more than USD 100 billion in 2020 (8) . Large sums are spent on marketing and advertising, much of which is aimed at children. The sugar industry also affects global health through worldwide supply chains, financial support for institutions and lobbying of health policy decision-makers (2) .
Resisting the sugar industry's marketing should not be left to the individual. Global cooperation at the political level is needed to control the influence of commercial actors on what we eat and drink. Together with equal access to dental health services, this is crucial for improving oral health, and thus public health.