Just as with any other bone or muscle group, your jaw will not function properly if you do not exercise it and nourish it. People with degenerative diseases or hereditary conditions can have their jaws wear out more quickly because of their serious medical conditions and may require reconstructive jaw surgery. There are a few exercises that you can do, in addition to eating a healthy diet, to help increase your jaw bone density and your muscle strength.
Chew as much as possible. The action of moving your jaw up and down with the combination of pressure on the upper jaw can help to increase jaw bone strength and density. In addition to chewing your food well, chew sugar-free gum between meals.
Open your mouth and stick out your tongue. Move your tongue back and forth one time on each side, and then pull your tongue back into your mouth. Close your mouth. Repeat as many times as possible in two minutes. Do this exercise throughout the day whenever you think about it.
Open your mouth slowly as far as you can. Gently and slowly move your jaw to the left as far as is comfortable and then to the right as far as comfortable. Slowly bring your jaw back up and apply a small amount of pressure to your upper jaw. Do two more repetitions to complete one set. Repeat this exercise throughout the day, doing one set each time.
Sing random notes of "la, la, la" at various pitches throughout the day. This will get you opening and closing your jaw and the different vibrations of your voice will help you increase the strength of your jaw muscles and density of your jaw bone.
If any of these exercises cause pain, consult your dentist.