What is the average biting pressure of an adult human?

One of the very few - perhaps the only - creatures whose bite pressure can be measured fairly accurately is human beings. The average biting force of an adult male human (male because, in general, we lugs are bigger and have proportionately thicker masseter muscles than females) varies between 45 and 68 kg - although forces as great as 159 kg have been recorded for Inuit males (squeaky-voiced, ear-biting tough guy Mike Tyson, please take note). The Dental Science Handbook published by the American Dental Association (1970) gives bite pressures by humans as great as 15 tons per square inch - 83% as strong as the greatest pressure recorded thus far for any shark. No wonder human bites are often so devastating - we have short jaws, powered by thick masseter muscles and armed with relatively blunt, chisel-shaped incisors. So play nice, kiddies!

from:

http://www.elasmo-research.org/education/topics/r_bites.htm

-D