Most dental plans fall into one of two categories: the DHMO (a managed care program) and PPO (preferred provider organizations). The two are both considered forms of managed health care insurance, but they operate using slightly different management methods.
Another route to consider is a payment plan through your own dentist. Many dentists, tired of trying to deal with the delays, limits, and red tape of insurance plans, are offering their own payment plans which allow you to purchase services using incremental payment strategies.
Some even allow you to put money in over time, so that there will be money there when you need it. Be sure to ask your dentist what forms of plans he offers, and get any instructional material he has available so that you can compare his plan with other options open to you.