I have TMJ issues. When I feel fullness in my ear it is usually my left side, the ear with constant tinnitus. Interestingly enough I am able to manipulate the fullness by pulling on the upper portion of the ear and opening and or opening and closing my jaw.
This "fullness" feels like it's originating right in the mandibular joint.
The area also feels numb or "dead" or "stuck" it's odd.
In theory the fullness should be emulating from inner ear and physical manipulation of the ear should do nothing, but it does.
I believe that TMJ can somehow effect inner ear but have not seen any good solid convincing research on the topic.