Lots of experience here. For future reference or anyone reading.
Milkshakes. Eat them with a spoon if you aren’t allowed to use a straw. If you find you’re sensitive you could always ask for less numbing. They might have gone above the minimum to be safe and ensure you’re comfortable.
It would wear off pretty quick for me though my appointment might be an hour and would be gone after 3 hours. And I was able to function mostly normally even while numb. I would smile a lot in the mirror too cuz the crooked smile was amusing. Eventually even that wasn’t crooked anymore after so many appointments.
Light cardio exercise like a going for a brisk walk, pacing at home, tidying up, etc. It doesn’t have to be enough to sweat, just enough to get the blood pumping faster.
I completely misunderstood your question and was trying to figure out who eats the cheeks and gums of an animal and was going to suggest putting them in a bag in the sink under running water.