The most common myth about 'pit bull' dogs is that their jobs lock. This is untrue.

Breeds like the American Pit Bull Terrier do have very powerful jaws, and this is where this myth comes from. However, the jaw does not 'lock' - and you cannot get the jaw to 'lock' through abusive actions such as breaking the jaw. (yes, we have heard from people who believe this is how you get a 'locking jaw' and we have incredibly sympathy for any animals they own.) 

On this topic Dr. 1. Lehr Brisbin of the University of Georgia wrote:
"The few studies which have been conducted of the structure of the skulls, mandibles and teeth of pit bulls show that, in proportion to their size, their jaw structure and thus its inferred functional morphology, is no different than that of any breed of dog. There is absolutely no evidence for the existence of any kind of "locking mechanism" unique to the structure of the jaw and/or teeth of the American Pit Bull Terrier."

The 'pit bull' has powerful jaws, but they are not alone in this. This is yet another myth - that 'pit bulls' are more dangerous because they have the most powerful bite. Most large breeds and cross breeds have a very strong bite, and even smaller dogs can inflict a bite powerful enough to kill. Any dogs can be dangerous in the hands or an irresponsible, negligent or abusive owner.