Toothbrushing thoughts: DS hated mint and all the strong flavors or normal toothpaste. Once we found Tom's of Maine Silly strawberry, things got better. Do you know how hard it is to find a non-mint toothpaste?
DS has sensory issues and the only thing he hated more than brushing was going to the dentist. I finally told him that the natural consequence of not brushing was going to the dentist more for professional cleanings. Then I let him choose. And he chose to brush!
I think if there is an area that you have completely locked horns on, I would probably actually just take a break, give up on it since the ongoing battles tend to entrench people deeper in their positions. Once things have calmed down (after a few days) go over the situation. One of my favorite phrases with DS is "if you were the mom and I was the kid and I wouldn't brush my teeth, what would you do?" That puts their considerable brain power to work on your side!
And remember, he probably will start brushing his teeth eventually, at least by the time he has a girlfriend