Could you get welfare for a while? Just long enough perhaps to have the dental work done? Alternatively, Dental schools perform low cost work, done by students, but closely supervised by a fully qualified dentist/teacher?

It's important for teeth to be in good shape-- and not just for cosmetic reasons. Gums that become infected can stay that way for a long time, which can cause subsequent infections in other organs, particularly your heart.

My wife, for instance, is generally healthy, but she must take antibiotics before ANY dental work, including cleaning. This because she has a minor heart defect that is susceptible to mouth related infection.