Here is the position statement from ACVD:
AVDC Position Statements | AVDC - American Veterinary Dental College
Forgot that the other advantage to having a vet do it is intubation. I bet the cuffed endotracheal tube keeps some of the bacteria from distributing through their symptoms (when my teeth are scaled, I'm told to rinse and then it gets sucked out rather than swallowed).
That was it - a broken jaw.
Then there was another one - finally had a vet do it. The visable surfaces were white, but the dog lost tons of teeth because they are destroyed under the gums.
And polishing after does create a smooth surface. It's harder for plaque to stick. No polishing just makes them more susceptible to problems. After a cleaning under anesthesia, the teeth start to accumulate plaque in 15 minutes. If there is really a place for it to stick, it just makes it worse. Sooo that is why I skip doing it at home. I'd love to be able to, but just won't. I don't think it's healthy for my pups when thinking about what is going on systemically. I think if the visable surfaces need a cleaning, then the subgingival area does too. Doing one and not the other is leaving tartar behind and leaving their bodies open to bacterial issues. But that is JMO.
Vet techs do cleanings here, but my vet does the exam. I wouldn't insist on the vet doing the cleaning anymore than I would insist on my dentist cleaning my teeth instead of a hygienist. IMO, they are trained to do this, and if the vet is doing the exam and reading the xrays that is fine with me. The prices probably reflect the fact that even if a tech is doing the cleaning, the vet has to block off their schedule to be near their anesthetized patients, do the exam, etc.