Matthew Rose of Restorative Dentist The Implant Center Hove & Hayward's Heath explained everything to Express.co.uk.
He said: “The queen mother was born in 1900; therefore, at a time when dentistry, as we know it today, was completely different.
“Dentistry was more invasive because it mainly consisted of extractions if a tooth had a problem, and the preventive side we all now know about, like fluoride, was not known.
"Modern cosmetic dentistry, with its bright white smiles, was simply not available to the queen mother for most of her life."
The queen mother might have opted for dental work later in life, but it seems she didn't care about any adjustments.
Matthew added, "Although an aesthetically pleasing smile might be available as an option for her when she grew up, maybe that was something that wasn't important to her."
Matthew also revealed how Prince William had subtle cosmetic dentistry after losing a tooth at a friend's wedding.
He said: “After 2014, when it was rumored that he had lost a tooth, the right upper central incisor (UR1) seems lighter and more aligned – just like the upper lateral incisors.
"It seems to me these teeth were crowned or clad."
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