Seeing a dentist

( Denis gets a toothache, so he goes to visit the dentist, Dr. Thomson.) 
A: What's the matter with you? 
B: I've got a bad toothache, Dr. Thomson. 
A: Please sit down. Now open your mouth and let me check your teeth. 
B: An upper tooth on the left. 
A: Oh. It's here. There is a deep hole in it.
B: You will have to pull it, won't you? 
A: I think it necessary for you. 
B: Will it hurt? 
A: Only a bit. I'll give you an injection of anesthesia.
B: Will you pull it out immediately? 
A: I'll wait for a moment till the drug is taking effect. 
(Twenty minutes later, the dentist finishes his work and takes away the absorbent cotton.)
A: OK. How are you feeling now? 
B: (Search the hole with the tongue.)
Oh, my God! You pilled out the wrong tooth!