From
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3872851/
"Although good follow-up data exist for implants, the question of true long-term success and/or survival still needs to be answered. However, a recent study provided 20-year data on implants with a rough, microporous surface in partially edentulous situations, with 72 of 145 original implants remaining for follow-up after the exclusion of deceased patients and those lost to follow-up (Chappuis et al., 2013). Of these implants, 68% had been without technical complications. The success/survival rate was 75.8%/89.5%. Still, these long-term data are scarce. Even after the completion of craniofacial development, implant placement in young adults may therefore be viewed with caution, since restorability options in areas where implants were previously lost have yet to be explored on a higher evidence level."
"[At 3 years after installation] the survival of implants placed by inexperienced practitioners was 73.0% compared with 95.5% by implant specialists (Morris and Ochi, 2000a,b). A comparison of tooth survival rates after endodontic treatment by endodontic specialists vs. general practitioners, in a multi-center study consisting of 350 teeth that met the inclusion criteria, showed a difference of only 98.1% vs. 89.7% (Alley et al., 2004)."
If you want dental implants, don't go to a normal dentist for dental implants. Read about implant specialists.
Implants do not support the full load that natural teeth do- you should avoid using them to avoid failure. If you're young, don't consider them, they won't last your life unless you are very lucky. 20 years out from now 1-2 of the four implants will likely have failed or suffer complications (e.g. chronic infection or too much bone loss).
Consider consulting with an endodontist or two, at consultations of $25 or so each (in the U.S., in the U.K. I have no idea). They may be able to use their increased skillset to salvage your teeth, where a general practitioner may not be able to.
I think in the UK dental implants are not covered under the public health care, they must be paid for privately. You'd have to get quotes from practitioners, it is up to them how much they'll charge you for dental implants.
