But orthodontists are concerned about the potential risks of these, which include damage to the roots of teeth, gum recession, loose teeth and teeth that need to be removed.

Customers are required to take teeth moulds themselves and work progressively through different sets of aligners sent to them in the mail, which move their teeth over time. A remote orthodontist oversees their progress through photos.

A lot of people underestimate how complicated changing teeth is because it ultimately affects your bite, which affects your jaw and your jaw joint and the muscles of your face.

A survey found 35 per cent of orthodontists who responded had treated a patient in the past 12 months following failed use of at home aligners.