Pitties' jaws are the same as other breeds.
Statistically, my guess is, it's a very small percentage of Pit Bulls... that are ever involved in aggressive attacks.
The problem with Pit Bulls, regardless how [few bite], because of their jaw anatomy, when they do chose to bite, it immediately becomes a life and death event.
I know Pits that are great pets, & some breeds... not known for aggression that are just plain nasty, all the time.
Like most other breeds, the vast majority of Pitties live their lives out & never bite anyone badly - minor nips or a single puncture when provoked, sure, but knowing how much cr*p ppl pull, & the dumb stunts, rude & intrusive or scary behavior by humans, it's impressive to me how FEW bites dogs deliver.
But Pitbull jaws are no different than other breeds' - they don't lock; they have big muscles on their jaws, necks, & connecting to their chests, but so do many other breeds. Their BEHAVIOR can contribute to the level of damage, if they
grip & shake! - but other breeds do that, too.
any dog 30# or more can deliver a severe bite to an adult human; depending on where the bite is, a single bite can be fatal - the foreign businessman who was bitten by a Moscow street-dog that he tried to kick was a case in point, the dog punctured his femoral artery & he bled out, right there on the street.
Any dog of whatever size can severely injure a young child - a Pomeranian is the smallest breed that i know of, to be involved in a fatality.
The baby who was killed was about 6-MO, & was
left in the care of a 15-YO girl, while Mom & Dad went out of town! -

everything about that case was weird.
- terry