Well over half the earth’s population has dodgy teeth and gums, according to worldwide research led by university professors in east London.

Nearly four billion people have bad oral health—partly because we’re all living longer, a three-year study by the University of London’s Queen Mary dental college at Whitechapel has found.

“We are facing serious problems of untreated conditions causing toothache and preventing people eating or sleeping,” said Queen Mary’s Prof Wagner Marcenes who led the worldwide research. “This doesn’t even include small cavities or mild gum diseases.”

Oral diseases rose 20 per cent in 20 years, mainly due to population growth and people living longer, the study concluded.

“Ironically, the longer we keep our teeth the greater the pressure to treat them,” Prof Marcenes added.

“Our findings are set to shake up health priorities—major efforts are needed to prevent gum disease and tooth decay.”

The research involved 500 scientists around the world carrying out a systematic assessment of data on all diseases, including dental records going back 20 years.