I have been having dental work in Thailand for many years, I have had fillings, extractions and just a few weeks ago had a bridge fitted. I go there on holiday every year and go for regular check-ups, the cost is a fraction of what i'd pay over here.
I reckon that if you booked a two week holiday with a half decent hotel and had your dental work done, it will turn out cheaper than straight forward work in the UK.
The one that I use is very clean, sterilised instruments etc. I first used him about 15 years ago when he worked in a hospital over there, then he started his own dental practice, so I went with him.