Factual error: In the scene in the lab where they notice the porn actress's wisdom teeth have not erupted yet, they show her lower jaw with the wisdom tooth just under the gum, but say it is 5 cm under the gum. I don't know about you but if my wisdom tooth was 5 centimetres under the gum, it would be hanging out the bottom of my jaw. (FYI, 5 cm is almost 2 inches.)
Plot hole: Alex determines the actress is only about 18 because her wisdom teeth haven't erupted yet. The problem is they don't always erupt, I'm 32 yrs old and mine have never erupted.
Answer: Yes, sizes of jails differ.