Hiya
I have many many family relations (and friends) in the US, Canada, India and UK who work as dentists (can you tell we're an Indian family?!!)
Talking to them all there really isn't that 'much' of a difference in practice methods or quality of care. The 'stereotypical' all 'english people have bad teeth' thing is a leftover from hundreds of years ago and is a part of the usual rivalry make fun of each others countries type thing!
Its the 'system' of care which is more in the direction of what you're getting at. The NHS is good, no doubt, but it's also completley over burdened and creaking at the seams so to speak. Better responses and accessibility can be had by going private - as previously mentioned by others. This doesn't mean you should discount the NHS system, just be prepared to have the possibility of a longer wait or administration crap to get through to get your care and again, sometimes it can be quicker than you'd imagine.
From memory at a news report, I think all water in the UK has Flouride added although I think there are varying levels/amounts. I may be wrong on this, but I was under the impression it has always been done since around the 50's ..
good luck
Dennis! West London & Slough UK!