Asked by: Les Reeves, London
Sucking a thumb or dummy up to the age of two is fine, but several studies have shown that beyond that, there is a risk that the front teeth can be pushed outward, or the side teeth shifted so that the top and bottom sets don’t meet. A 2001 study by the American Dental Association found that about 20 per cent of children who suck their thumb beyond the age of four have a misaligned bite.
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