Minnesota was working out to about $368k for all 4 years, with tuition to rise in the near future. I think they're looking at something like $100k per year for OOS, which is C R A Z Y. That's the main reason I turned down their interview...even if I somehow managed to get in, the cost isn't worth it. ASDOH also had the cost of $368k, but I think that's wrong for ASDOH. Just because you don't need the full amount of money they're offering for living expenses. You could live off $24k EASY (this is being too generous) and they gave $30k per year. So that would push ASDOH's costs down to $342k.
I'm having a hard time deciding between UMich and ASDOH, so for me, the costs aren't really in play because they're very close. So I guess the next step is to really look at which program is more suited for you (and me). You'll have to see if you want the college town (UMN) or just a couple buildings of graduate students (ASDOH), and whether you want the full spectrum of dentistry available (specialties, etc) or general & ortho at ASDOH. Good luck!