TMJ or temporo-mandubular joint syndrome is an inflammation of the jaw joint just in front of the ear. It can be caused by abnormalities of occlusion (the way your teeth come together). The chief symptom is pain in the ear when your ears appear normal upon examination. Tinnitus and vertigo can also occur. It usually occurs in novice divers who clench their teeth, occasionally biting through the mouthpiece. Treatment includes bite adjustment, management of dental problems and the use of orthodontic mouthpieces. Heat and anti-inflammatory drugs are helpful.