Dental X-rays don’t work as a means of finding out a person’s age.
The British Dental Association describes them as “ineffective”, and there’s a large margin for error. The Home Office does accept voluntary tooth X-rays as evidence of age in an asylum application.
“The issue of X-raying children's teeth, it wouldn't work. The experts say it wouldn't work.”
Angela Rayner MP, 21 October 2016
Dental experts say that tooth X-rays aren’t a particularly precise method of establishing a person’s exact age, although they can help narrow it down. Their concerns are moral as well as scientific.
The British Dental Association has described such tests, in response to the suggestion that young people coming over from Calais should have to take them, as “ineffective, inappropriate and unethical”.
It says that “wisdom teeth can erupt from the age of 10, and do not appear in some adults. These x-rays can therefore only provide an estimate of a patient's age range”.
Professional guidance for children’s doctors says that:
“estimates of a childs physical age from his or her dental development are accurate to within + or - 2 years for 95% of the population… for older children, this margin of uncertainty makes it unwise to rely wholly on dental age”.
But that doesn’t mean it’s a useless tool. Showing that somebody is very likely aged between 21 and 25, say, is a good indication that they are over 18.
Home Office guidance says that asylum applicants will sometimes submit dental tests as evidence that they are a child. “There will be cases where such reports should be given considerable weight—for example because the applicant’s claimed age is within the possible range”.
But dentists and doctors see a difference between a voluntary test and a state-imposed one. X-rays, after all, involve exposure to radiation. The BDA says it has resisted efforts by the government to make asylum seekers “undergo a medical procedure without their informed consent and without any planned clinical benefit” for over a decade.
This factcheck is part of a roundup of BBC Question Time. Read the roundup.