Gaten Matarazzo, who plays Dustin in Stranger Things, opened up about his disability on The Jonathan Ross Show last week.
He said he has cleidocranial dysplasia, which is a condition that affects the growth of the bones.
Matarazzo said: "It's a condition where you are born without your collarbones; I don't have any. It affects your facial growth, your skull growth, it affects your teeth. That's why I don't have any – these are fake – I have teeth but they're all baby teeth."