I use the local DD plan and PrimeStar Dental ( underwritten by Security Life); it has up to a 2K annual max. Major restorative and ortho are on the 3 year schedule up to 50%.
One dental Plan I like is Encore Dental but they do not use agents yet. You might want to check their www occasionally.
I really like the dental plan that World insurance offers. The wait period on it is somewhat long on major services, but it covers 100% preventive, 80% minor, 50% major, its indemity, they allow it to stay after age 65, and the price for 2 adults and children is same no matter how many children you have.
I've got 10 or 12 on the books, they never cancel.
This is what I typically use for individual: Spirit Dental. FYI: it's an indemnity plan, PPO only offered for group plans. However, I haven't had any issues with it.