The new contracts came into effect in April, 2006. Basically, it simplifies how dentists are paid by the NHS and also replaces the old billing system. We were just signed on as new patients and we went for a check-up and registration. It is a three tiered system now. Check ups, cleaning, and simple work, and X-rays are 15.00 GBP, two or more fillings etc are 42.00 GBP and and bridgework, crowns, more complicated procedures are 189.00 GBP.
I went for check up and registration, and paid 15 GBP. The next visit I had one filling and didn't pay anything. If I needed more work, I would pay the next fee and that would cover how ever many visits it takes to complete that treatment.
I know I have simplified it loads, but basically a google search for dentists NHS would bring up more specifics.