Does anyone have recommendations on finding a dentist in Great Britain this summer?

It will depend a lot on where you are: dentistry in the UK is in a very bad way at the moment (I know, I know -- but even worse than the reputation of English Teeth suggests...), and the pandemic has made things worse.  In general, though, my impression is that things are better (or less bad!) in southern England than elsewhere.

What I'd suggest is using the NHS dentist finder to locate practices in a location convenient to you: https://www.nhs.uk/service-search/find-a-dentist  You will find that most places listed there will have a note saying that they aren't taking on NHS patients at the moment; however, in many cases these practices will still be able to take on private patients (this is because of the very crazy way that dental care is organised in the UK: I will save you the rant, though!).  So, if you find a practice which looks ok, then it will be worth getting in touch to see if they will take you on as a private patient.  (This shouldn't cost a huge amount, certainly for straightforward things.)  You might find that there's quite a wait for an appointment slot -- but again this can vary hugely (my dentist/hygienist at the moment has about a 4 month wait time for non-emergency treatments; but I know that elsewhere people have been able to make appointments within a few days...)

(Oh, a ps to say: the link I gave above just covers England.  For Scotland, you need this one: https://www.nhsinform.scot/scotlands-service-directory/dental-services/

And for Wales: https://www.wales.nhs.uk/ourservices/findannhsdentist

Healthcare is one of the things which is devolved to the various nations of the UK: it's all the NHS, but it operates slightly differently in the different countries...)

thanks so much for the information!  I did find the link for the dentist finder but so far no luck.  I’ll keep looking.

Good luck!  I hope it isn't too frustrating a process.  (My hunch is that you might have better luck in larger settlements, and with the bigger dental practices -- but it is pretty much a lottery at the moment, I'm afraid...)

Good news!  We’re booked!  In Abergavenny, Wales.

Ah: that's great news!