Nearly half of the world's population, or 3.5 billion people, suffer from oral diseases, the majority of them in low- and middle-income countries, the World Health Organization said on Thursday.
The most common oral illnesses are tooth decay, severe gum disease, tooth loss and oral cancers, with untreated tooth decay affecting nearly 2.5 billion people, the United Nations agency said.
About 380,000 new cases of oral cancers are diagnosed every year, it said.
WHO cited large out-of-pocket expenditure and the unavailability of highly specialised dental equipment in primary healthcare facilities as two of the reasons for the high prevalence of oral diseases, especially in poor countries.
"Oral health has long been neglected in global health, but many oral diseases can be prevented," said WHO Director-General, Tedros Adhanom Ghebreyesus.
The agency suggested countries include equitable oral health services as part of their national planning and integrate oral health services into their primary health care models, while also improving access to affordable fluoride toothpaste, among other measures.