Wow - Y'all need to chill. All the information you need will be provided to you during orientation. And for those of you who are pre-purchasing scrubs, you may find out that you can't wear them. My school requires us to have scrubs that are embroidered/have unique shades that you can't just buy on Amazon easily. Patients aren't going to take you less seriously because you are/are not wearing a white coat or scrubs. You're not treating the well-to-do, but indignant patients on Medicaid or those without insurance who can't afford a regular dentist.
First year, people wore whatever they want (sweats were fine) and from then-on, it's scrubs 100%. No professor will care what you wear to a microbio class and even if they disapprove, it's not like they're going to fail you just because you wear yoga pants or something. Everyone wears scrubs: predocs, residents, facility, etc. I agree with the above, save your loan money. It's not free and it needs to be paid back, post-tax, with interest.
Relax. Enjoy your last few weeks of freedom. Soon, you're going to realize that it doesn't matter what you wear, what matters is how you treat people and how your perform.