Loan money was dispersed after classes began, and this wasn't a problem for students as far as a I know. Other expenses: none directly school related that I can remember other than textbooks. But really, besides Gross, don't waste money buying textbooks. You don't need them and you won't have the time to look at them anyways.
Lunch: You have at least an hour each day for lunch. Some students pack their lunch while others buy. If you decide to buy (not enough time to pack or too tired/lazy) you have a lot of options. Cart food is great (can get pricey though) and there's always the hospital (cafeteria, einstein, wendy, chick fil a, subway, etc, ABP, etc. The hospital cafeteria is actually pretty popular among students because the food is good/cheap.
Favorite class was operative dentistry lab because you actually do dentistry! Least favorite class is Evidenced based dentistry (you'll see why when you take it).