A large number of dental practices in the Boston area offer specials for students. These might be "back to school" specials or offers for services at a discounted price with a coupon. For the most part, these specials and coupons cover cleanings, x-rays, a consultation with the doctor, and a diagnosis for treatment (with estimate) for new patients only.
Some coupons offer services, such as cosmetic dentistry, for a discounted rate: 20% off of the cost of tooth whitening, for instance. Or, they might offer "braces at no money down."
Students can find these specials and coupons posted on flyers around the BU campus, in coupon mailers delivered to their home, and in various news publications/magazines.
Buyer beware on these deals; research them and ask questions about hidden costs and the cost of subsequent treatment you might require.