for those of you whose parents are loaning you money for school, keep in mind that the government will consider this loan a "gift" if no interest is charged (and likewise if a very low interest rate is applied that is nowhere close to market standards). What does this mean for you and your parents? Well, your parents can gift you up to $13,000 per year each, that means if you have 2 parents, they can give you $26,000 per year without having to pay gift tax on it. Anything over that, or over the lifetime limit of 5mil, will be taxed HEAVILY (although I believe tuition payments are not considered a gift as long as they are paid directly to the school). The last thing you want in dental school is the IRS knocking on your door demanding payment of taxes on the money your parents loaned/gifted you.
Furthermore, if you take an interest free loan from your parents, and pay it back over however many years, you really are not repaying them the true value of their money when you account for inflation. Considering over the past 30 years or so, inflation rates have been about 3-5% per year, you need to insist on paying the loan back with interest to account for inflation. Consider this-if you take a loan from your parents for $300,000 (a reasonable estimate for a mid priced private school in a city with very low living expenses), and you plan on paying them back within 10 years of graduation (14 years total), the actual value of that money when you account for inflation is about $420,000. If you only pay them on the initial loan you took out with 0% interest, you are actually shorting your parents $120,000!!! And that is not even accounting for the significant investment income your parents will lose upon dishing out that $300,000 "loan".
In all honestly, if in the future I had the capital to fund my future child's professional education in cash, I would do it in a heartbeat. I think most parents would want to do that for their kids, even if it meant sacrificing their nest egg and delaying retirement. So you might have to be the practical/grown up one in this conversation and insist upon paying your parents the loan back with interest equivalent to what you would pay to the government through stafford and gradplus (6.8 and 7.9%). That way, their money is still outpacing the inflation at a rate which is actually a pretty decent return in today's market, and the government isn't going to be getting rich off of you.
....i too sometimes wonder how I ended up in dental school and not finance.