Kate Middleton smile charms the watching world.

But did you know that Kate Middleton's beautiful smile comes from an Orthodontist who works in London, Geneva and Paris.

Dr. Didier Fillion, the French-born orthodontist has specialized in invisible braces and has the Royal Princess as a patient.

Kate visited Fillion Wimpole Street consulting rooms for a teeth makeover. Fillion applies braces to the back of the teeth where they could not be seen.

Kate Middleton
Briain's Middleton leaves following the wedding of Parker Bowles and Lopes in Lacock in west England Reuters
Kate Middleton
Britain's Prince William's girlfriend Kate Middleton smiles during the Sovereign's Parade at the Royal Military Academy in Sandhurst Reuters
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Britain's Prince William and his girlfriend Kate Middleton watch the England vs. Italy Six Nations international rugby union match at Twickenham in London Reuters
Prince William and Kate Middleton
Britain's Prince William and his girlfriend Kate Middleton react during Six Nations international rugby union match against Italy at Twickenham in London Reuters
Kate Middleton
Kate Middleton Reuters
Kate Middleton
Britain's Kate Middleton, girlfriend of Prince William, attends the first race on the final day of the Cheltenham Festival horse racing in Gloucestershire, western England Reuters
Kate Middleton
Middleton, girlfriend of Britain's Prince William, and unidentified friends react to the first race on the final day of the annual Cheltenham Festival horse racing in western England Reuters
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