Why does chewing gum cause teeth pressure?

Does not shatter: Some foods that you would think are soft actually exerts more force on the teeth than hard crunchy food. Gum for instance, as you load gum with bite force, the force remains linear and focused on the two teeth occluding on it, no matter what the force exerted on gum, the gum just compressed and stays between the teeth. A crunchy food shatters and clears the occlusal surface at less force.

Chewing: Your teeth must exert presssure to chew anything. If they are hurting or sensitive when you chew gum, they are trying to tell you something is not right. See your dentist to have the problem evaluated and treated.