UPDATE - 1 year, 9 months after my original post I've now just qualified as a dental nurse!
After posting, I got my first Hep B vaccination, bought a copy of Levisons, and researched dental practices in my area. I emailed my CV/Covering letter to about 10 of them speculatively explaining that I had no experience, but bags of enthusiasm, and got 3 interviews out of it!
I found being that bit older with more life/varied work experience an added benefit for employers.
During my training I gained experience in preparing for and assisting clinicians with dental health checks, restorations, prosthodontics, orthodontics, endodontic and hygiene treatment. More recently I have begun setting up for and assisting with dental implant surgery, bone grafts, soft tissue grafts, PRF membranes, and laser periodontal treatment.
For me, changing my career and retraining as a dental nurse was absolutely the right thing - I enjoy my job and look forward to specialising as an implant nurse. Their are different routes to take in Dental Nursing, depending on what you enjoy - so if you're seriously thinking about it, give it a go!