Have you gone to
Pre Login listed in the back of the plan's card? From their you can, after doing a bit of drilling down, download a list of providers for your plan which includes dentists.
Unfortunately this list is sometimes out of date so you have to check with the dentist directly to be sure. And there may be some dentists who do support the plan but are not on the list.
I'm using The Villages UHC Advantage but the dentist I go to doesn't accept it. But that is the dentist I've found that does a good job keeping my teeth in good shape.
So, yes, I'm paying the dental bill myself. The UHC plan, at least the version I have, only covers routine preventive work like exam, cleaning, that sort of thing. If you anything beyond that, like a filling, that comes out of your pocket.