Phys.org has a story about the strength of a Tyrannosaurus rex bite. This story describes research which appeared in a paper published in the journal The Anatomical Record.
A Tyrannosaurus rex could bite hard enough to shatter the bones of its prey. But how it accomplished this feat without breaking its own skull bones has baffled paleontologists. That's why scientists at the University of Missouri are arguing that the T. rex's skull was stiff much like the skulls of hyenas and crocodiles, and not flexible like snakes and birds as paleontologists previously thought.
"The T. rex had a skull that's 6 feet long, 5 feet wide and 4 feet high, and bites with the force of about 6 tons," said Kaleb Sellers, a graduate student in the MU School of Medicine. "Previous researchers looked at this from a bone-only perspective without taking into account all of the connections—ligaments and cartilage—that really mediate the interactions between the bones."