I ran across this experiment the other day and though it's pretty horrendous that they subjected a monkey to this, it got me thinking: https://www.facepulling.com/proof-moving-the-maxilla-is-possible-in-adults/ The monkey's maxilla was pulled forward with 500 g of pressure 24 hours a day for 3 months which caused the maxilla to move forward quite a bit. My question is if 500 grams of continuous pressure was able to do this, does anyone know about how many grams of pressure the average tongue can exert?
There are a few various graphs and studies you can find on Google. This is quite a typical illustration:

The study from which the above graph was produced is likely based on mostly untrained tongues. Frequent training multiplies the strength of the tongue by 2-3x.

Based on these graphs, it'd probably be fair to say that you'll eventually get to a point where maintaining 500 grams of continuous force throughout the day shouldn't be hard.
Thank you! That's exactly what I was looking for.