Temporomandibular joint disease, or TMJD, is a very common disorder that affects millions of people in this country. The most common symptoms are ear pain and headaches. Other less common symptoms that are described are ringing, buzzing, ear fullness, sound sensitivity, popping and clicking. A paper published in April, 2008 issue of Archives of Otolaryngology - Head & Neck Surgery described a relatively high incidence of theses "aural" symptom in patients seen in an academic TMJ clinic. They reiterate and agree with other authors' hypothesis that local inflammation of the jaw joint, due to it's proximity to the ear structures, can aggravate all these problems. In the end, no one really knows why these symptoms occur. As in all scientific papers, they can only show association, but never prove cause and effect.
Let me propose one possible cause for these effects: People with sleep-breathing disorders (obstructive sleep apnea and upper airway resistance syndrome) all have various degrees of nasal inflammation with ear and sinus pressure problems, TMJD, and headaches. If you have nasal inflammation with partial blockage of the tube that connects the back of the nose to the middle ear (Eustachian tube), then you can imagine that you may feel ear fullness, hearing loss, popping or clicking. If your senses are heightened due to a physiologic stress response due to inefficient breathing during sleep, then you can hear noises in your ear or be sensitive to certain sounds or voices. Neurologic stimulation of the various structures can aggravate jaw muscle stimulation and spasm, or even ear or sinus fullness. This is similar to what occurs in a migraine attack. Various papers have suggested that a migraine attack can occur in any part of the body that has nerve endings, so in theory you can have a "migraine" attack anywhere in your body.
This is one of many papers that describe observations between one specific condition and it's symptoms. Their findings and observations are accurate, but when viewed from the more holistic perspective of the sleep-breathing paradigm, you may be able to make sense of all of these various interpretations all that much more. After all, there's really no point in looking at all this research without having an overall perspective to interpret it from.