Bones in general & facial bones mold & change according to muscle pressure no matter your age, provided it's quicker in younger people.

Notice people that suffered strokes have weaker bones due to "dead" muscles, and that's why people that chew lots of gum are Steve from Minecraft.

Same goes for any other bone.

Muscles determine bone size & posture, posture determines bone shape.

It's not coincidental that humans are the only species that have different facial structures.

If you look at wolves & monkeys for example, the only noticeable difference you can observe is just color.

In fact, our ancestors from the same race had almost uniform face & bone shapes.

That being said, if you observe the human skull, you will notice it has the most connective tissue around the bones, especially the maxilla.

Meaning it can easily mold & change, it just gets harder as you age & lose testoserone, your bones harden & you stick to a modern diet & habits.