I just had the vet out to do teeth on 3 horses here for training. I always have the teeth checked BEFORE putting a bit in a horse's mouth. You can check for wolf teeth yourself and see if there are any sharps cutting the cheeks or gums but a speculum is needed to get a really good look and for that I need the vet. The first was a senior A size stallion. I knew he had wolf teeth because I felt them and he needed a float. The second was a 7 year old mare, no wolf teeth but needed a float BADLY. The third was a 4 year old gelding. I hadn't felt any wolf teeth but he needed a float. He had been floated previously and as I hadn't found any wolf teeth I had started him driving already. A couple times he had thrown his head up which can be characteristic of a horse with wolf teeth.
The vet came. The stallion had wolf teeth which were about average size for a Mini, maybe an 1/8" high, fairly small and they had come through the gums. The vet floated the gelding and when he was done I said "no sign of wolf teeth yet?" He felt his gums and said no. Then we both said "wait a minute!" There were wolf teeth in there but they were so big both of us had mistaken them for molars - the vet had in fact FLOATED them! I have never seen such huge wolf teeth in a Mini, neither had the vet, and seldom are they even that big in a full size horse!
Because wolf teeth are not usually firmly anchored in the jaw, when a bit hits them they move and cause severe pain. I would not ever put a bit in the mouth of a horse with wolf teeth although occasionally they don't seem to cause any pain as Disneyhorse said, but of course you don't know that until you bit them and then it is too late!
The mare that I had floated had been bridled by her owner and is now having issues with the fear of pain she associates with a bit. She is getting better and better with it but it has taken some time.