Comments by "LancesArmorStriking" (@LancesArmorStriking) on "Blame Modern Diets, Not Genetics, for Your Crooked Teeth and Breathing Problems" video.

@wodasu It might have helped your jaw muscles but your jawline (how 'defined' it is) is determined by the angle at which your skull juts out from underneath your flesh. That's entirely genetic, unfortunately.
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Harry Garrett That has more to do with the integrity of each individual tooth, not the shape of their arch. The 'look' of your teeth is different now because your tongue (from not having needed to coax fibrous food down as you swallow) doesn't rest at the roof of your mouth. As you grow, your skull adapts to whatever forces are placed on it, so if you don't keep your tongue there, it will affect your breathing, which will affect your facial development. In adulthood you can't really change this (which is why I disagree with Dr Mew), but from ages 5-12 much can still be done.
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 @flakgun153 China?
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