The OP goes to an expensive private school so that means he/she will have >$400,000 in debt once he/she graduates. That also means >$6,000 in monthly loan repayment under a 10-year plan. Since >$6,000 a month is equivalent to >$72,000 a year, the OP will likely opt for a 30-year repayment plan unless he/she increases his/her efficiency and opens his/her own practice. If he/she chooses to continue on the 30-year plan, which no one should do, the OP will have paid >$900,000 in loan repayment. (Look at my thread on calculating loan repayment).
For your first few years out of dental school, an awesome salary is going to be >$90,000. Let's say it were $120,000 (unlikely). Depending on your state, your total taxes (Federal and State) would be $33,545.50 for Virginia. Under a 10-year repayment plan, you would be paying >$75,000 a year. Add these up and you get a loss of $109,495.50 per year. With a $120,000 salary, you're left with $10,505.50 to live off on. It's unlikely that someone would live off of such a low take home amount so you can assume that they'd opt for a 30-year plan until they increase their salary and then refinance to a 10-year plan. You would make less than a lot of highly-educated people if you went to a private dental school and if you tried to pay it off on a 10-year schedule.
I think there's a lot of options for these newly graduates from private dental schools. There's income-based repayment (it could be an awesome deal), National Health Service Corps., and unfortunately dental chains that pay reasonably high (I'm shaking my head at how expensive dental schools have caused newly grads. to seek employment at some of these unscrupulous chains).
How to make a nightmare come true:
1. Make more private dental schools
2. Increase class sizes
3. Increase number of highly indebted graduates subjected to loans
4. Have newly graduated dentists face a poor job market
5. Create pressure for newly grads. wanting a high paying job in order to pay off loans
6. Open more dental chains
7. Chains employ desperate newly grads.
8. Chains gain profit and open more offices
9. Chains replace traditional dental offices