Usually for complete dental implant treatment (implant + abutment + crown) in UK you have to pay between 2000 and 3000 GBP, depend on the dental implantologist where you decide to go.
If you decide to go abroad you can cut your dental implants costs from 50% to 70%. For example if you go for treatment in Bulgaria the price will be about 600 GBP without compromise of the quality. Even more the dentist you go probably will have much more experience than his colleague in UK, because he is doing 2 or 3 times more implants per year.For example if decide to replace your 4 missing teeth in you bottom jaw with 4 unit bridge over 3 implants the price in UK will be about 8,000-10,000 GBP. For the same dental implants job in Bulgaria will cost you about 2,100-2,200 GBP. If you add your travel expenses for 2 visits (300-400 GBP) and your accommodation expenses 7 nights x 50 GBP = 350 GBP (4 star hotel) the final treatment price will be 3,000 GBP which is only 30% of the cost in UK.
Now you understand why every year so many uk citizens have decided to go to Bulgaria for dental implant treatments.