Uhhhh......Crocodiles do not crunch bones with their teeth. They can not chew. Crocodiles and alligators use their teeth to hold their prey, while they hold it underwater until the prey drowns.
Once the prey drowns, it is usually stashed under a log or root, and left for a few days until it begins to decompose. This makes it easier for the croc to tear it apart into pieces small enough to be swallowed.
Whew, that's a relief. I was worried that they chewed.