The reason you have to go regularly with NHS dentistry is because there are very limited NHS resources. We only have x amount of UDAs per year, and any work above that we and the practice don't get paid and will lose money. So we have to know roughly how many patients we are getting every six months and how many UDAs we are likely to use that year. If you are on our books and don't use the service then you are taking up space that could be used by a patient that will come regularly, taking up NHS resources.
The other reason is because obviously with the NHS we get paid the same whether we do one filling or 30 fillings, if you come every 2.5 years there's a much greater chance that you are going to need more than 1 or 2 fillings. Which isn't really fair to us, or the practice. We would make a loss. And it's not fair on you because instead of a small filling you could end up needing a root filling or losing a tooth.
The third reason is obviously prevention, for example with regular scale and polishes to prevent things like gum disease, give you regular advice. Also think what percentage of the population will need a filling compared to the population who will have other health conditions. It's for your own benefit.
If we lose money we will eventually shut, and those UDAs won't get redistributed. Ergo less NHS dentistry. NHS dentistry doesn't make an aweful lot of money. I don't get paid 20 for a check up I get paid 8(1 UDA), if you need a filling I will make 24 (3 UDAs) but that could be for several hours work if you need multiple appointments or a root filling. If you need a denture I will make 100, but then there's probably around 60ish in lab costs bare minimum, could easily creep up to 100 and that's 4 or 5 appointments. A lot of the time I am working for free.
The rest of the money goes to practice running costs, which are high. There's obviously nurses to pay, material costs. Most of it is to ensure your safety as a patient. I think it's about 300 an hour to run one dental surgery.
If you don't want check ups and just want to go when you have a problem then you don't want NHS dentistry. You want private dentistry, that service isn't what the NHS offers. If you want NHS dentistry you need to use it regularly.