Your jaw joint is a diarthrodial joint which means it's like your elbow or your knee. There's a hinge, that's this part that's going up and down, and there's a cartilage in that joint. If you play too much tennis and you get tennis elbow. You get tennis elbow because you're wearing down the cartilage in that joint.
Individuals who clench or grind their teeth wear down the cartilage in their jaw joint. And the symptoms that you get include pain which can shoot directly into your ear or radiate to your jaw or your throat, or cause headaches and a sense of fullness or pressure inside your ear.
The most common cause temporal mandibular joint dysfunction is clenching or grinding your teeth in your sleep. And what basically happens is we all build up our anxieties during the day, and then when we go to sleep, we clench and we grind our teeth.
Your dentist can often examine the facets of your teeth and see that you're clenching or grinding.