My 12year old has been in & out of the vets for, what we were told, was a dental abscess.  It's in the middle of his top gum, just where the gum meets the skin.
He was sedated for them to have a look, gave 3 weeks of antibiotics, looked like it was getting a bit better but then didn't so he went in for the tooth underneath to be extracted, all on their advice.
This was around 2 weeks ago and he's still on Loxicom but they didn't send him home with any ABs.
He's had 2 post op checks and they're happy with the extraction site, although it's still open so they want to see him again on Friday.
However, today I've noticed the really bad breath is back and managed to have a little look.  The lump on the gum is still there and looks like there's a little pus there and he doesn't want me to touch it.
So, have we had the tooth out when it wasn't necessary, is it something more sinister or simply become infected & needs ABs?  Any advice or suggestions most welcome.
I really have no faith left in our vets (never see the same person twice, etc) but no other local practices are accepting new patients.

Well for starters, you absolutely must be able to trust your vet.  After close family relationships, a good relationship based on trust between owner and vet is, in my opinion top of the list.

And having had two (one unconfirmed) cases of oral cancer in my hounds, I'd need to be able to rule that out.   If the mass is still there, and hurting him, I'd not wait until next Friday but get him back for another examination - the only advantage of seeing a different vet in a multi-vet practice is at least you get a 'second' opinion!  I'd have expected him to be on a course of a/bs but I'm not a vet! 

I'd not like to say whether your situation is oral cancer, or not, but for sure, I'd expect a vet, especially one who has been treating this problem and done an extraction, to be able to diagnose and treat your dog.

Do you know why other local practices are not accepting new patients..... vets don't usually turn prospective clients away (unlike human dentists and NHS patients!!)

I cant comment on the medical situation except to say I would get him back ASAP. Pus sounds like infection.
  I have heard from more than one practice  that generally speaking there is a shortage of qualified vets and the ones we have are oddly very busy .trying to get appointments is almost as bad as the nhs .well maybe not quite. My cat is being referred to a specialist and the most convenient referral vet cant see her until 2022 as they are so busy . The one we are going to cant see us for 6 weeks .unusual for referrals
Possibly because of all the animals bought during lockdown ?
That may be why they arnt taking new clients

Other practices have been so busy that they just cant cope with any new clients, but I'm on their waiting list.
I've brought his appointment forward to tomorrow so will see what they say.

The vet I go to has two surgeries in the building. At the moment, instead of having a vet in each, they appear to have one vet who sees a client in one surgery and then moves to the other to see the next client whilst the first is disinfected. So they will only be seeing half the number of patients

>Do you know why other local practices are not accepting new patients...

We changed vets recently and I know there is now a waiting list there so we were lucky we moved when we did. As others have said it seems there is a shortage of qualified vets at the moment. Maybe there needs to be more universities offering courses in veterinary medicine.

We had a dog with a mass on his lower jaw. After exploratory surgery at our local (previous) vets we had a referral to the now defunct Animal Health Trust. Sadly there was nothing more than palliative care that they could offer.

If this was my dog I'd ask for a referral. If it's anything sinister it's better to have an early diagnosis then hopefully be able to start treatment.

I'd say it's antibiotics that's needed and I'm surprised they didn't give that to start with -it's so easy for food to end up in a wound in the mouth. If it was big, did they not stitch it? That's what I've experienced with both dogs and cats, an extraction of a big tooth has always meant it being stitched (dissolvable stitches) and then it has healed quickly.