Dental Students Debt Situations

Recently just accepted an offer to start DS in Fall '17 for the low cost of....>$335K without factoring in the killer interest. I believe I can take out around $40,000/year with 5.31% unsubsidized federal loans and then I'll need to cover the rest of the loans with GradPlus at 6.31%. These are serious numbers and I need to plan ASAP for my future.

I would like to join the military, but I had a medical condition that held me back from 4 year HPSP. I would need a medical waiver and a hell of a lot of luck to get a 3 year HPSP. Luckily I have very very competitive academic stats so that doesn't hurt.

Anyways, with this debt load, should I try to refinance my loans after dental school for a lower rate? How long should my loan plan be and can I save $ by paying off my loans before it matures?

As far as practicing out of school goes, I am willing to go to bf Louisiana if it meant that I can make $ to put towards a practice 1-2 years out of school. Speaking of becoming a practice owner, how am I going to get the finances to buy/start one if I have $450K+ debt in student loans.

Sorry for all the questions, I'm very worried because I don't have a plan.