The dental plans available on Healthcare.gov are not necessarily the best available. It is important to remember that, unlike the healthcare plans which can be generously subsidized by the government, the dental plans are unsubsidized. Furthermore, if you enroll in your dental plan at the same time as your healthcare plan, you wind up being locked into it.
Here are dental plans that you can enroll in OUTSIDE of the healthcare.gov market place. The first link is primarily for dental insurance. Many of the same plans that are on Healthcare.gov are listed here, but sometimes at lower prices. Some of the plans also include vision.