8 year horror tooth extraction

[MetalCutter]

I come here asking if you think this is acceptable or downright butchery.

We took our 8 year old to our trusted dentist. He was getting a tooth extracted and this was his first time with any sort of procedure. In a nutshell it went like this:

1. Give 2 injections either side of tooth, nice and slow. Our boy didn't flinch, whatever he was feeling.
2. Five minutes later give a 3rd injection. Our boy pulled a face but said nothing, he did good.
3. A minute or two after the 3rd injection, start pulling the tooth
4. Immediately our boy screams out in pain and says it's really hurting
5. Dentist does NOT stop
6. Our boy keeps on screaming and shouting out it's hurting
7. Our boy rises up in the seat, back arched, physically trying to escape the restraint of the assistant and dentist, screaming all the time. They restrained him while ripping out his tooth.

There was no waiting after the final injection
There was no testing of the tooth to confirm the anesthetic had worked properly
There was no initial gentle pull on the tooth to test for pain, just immediately go full steam ahead and rip the tooth out with our boy screaming from moment one.

I ASK YOU - IS THAT ACCEPTABLE DENTISTRY ???