Other than a tooth infection there is not much more pain than an ear infection and I have personally experienced both. Maybe the pain is so great because both are in the head area amply supplied with cranial nerves. I am amazed at what dogs tolerate and remain tolerant and loving. Chronic pain is exhausting.
I have had some dealings with pain. I had a vertebrae pushed out of place in 1966 and was in a steel and leather brace until 1981. I had two cruciate tears in 1959 and had to keep my knees wrapped until I was supernaturally healed by my father God in 1981. Unlike Fido the pain sometimes taxed my loving nature.
An ear infestation with ear mites has a characteristic look to the wax and 90% of the time ear mites themselves can be seen moving around in the ear with an otoscope by a veterinarian. The mites are easily killed with a commercial ear mite solution and some systemic treatments. The problem may be in resolving the infection left by their presence and cleaning out the debri left by their habitation. They don't seem to be very neat inhabitants like the occupy Wall Street crowd. The big thing with ear mites is to treat long enough through their life cycle so that when all the eggs are hatched out the young are killed and not able to reproduce. Another important aspect is to remember how contagious they are, so it's obvious they must have a presence outside the ear canals. Dogs and cats and other pets can share ear mites.
Often ears are infected by yeast brought about by lowered resistance due to allergies and long-term ineffective antibiotic use. The bacteria often will gain a resistance or tolerance to the antibiotic and it will not be effective, especially if it has an infrequent and not adequate exposure. I do not normally waste a client's money doing a culture and sensitivity lab test. The discharge of the ears, color and odor pretty much lets you know what the offending yeast or bacteria is and what antibiotic the bacteria will respond to.
There are several products that can control yeast. We make up our own called S & T Ear Solution which we have been pleased with for over 30 years. This is especially good for dogs with low grade infections and floppy ears which do not air well. Because it would burn an infected ear, the raw skin should be healed before the S & T Ear Solution is applied. It is also good to use like a swimmer's ear solution following baths and trips to the lake.
The type of bacteria infection in the ear dictates the type of puss that is excreted. The staph bacteria have a particular type of puss and the Pseudomonas and Proteus bacteria have a particular whitish-type puss and a sweet smell. These bacteria are fairly resistant to a lot of common antibiotics. They are what I would call garbage can opportunists that have gained ascendancy in the ear canal because the other bacteria have been killed off. Their resistance must be taken into account when designing a treatment plan. The lowered natural immunity of the ear has to be dealt with and the resistance of the ear increased. The A.C.C.E. Healing Gel has been good at accomplishing this feat.
Many of these allergies are constant in the environment in the form of food. The ears have a characteristic look which I call cellulitus. The lining of the ear canal is not smooth-skinned like it should be, but looks like the tread of a tire. This can be from a mild condition, looking like a street tire, all the way to more severe, looking like off-the-road mud grips. It is inflammation. This chronic inflammation can go on to cause granulation tissue (polyps) to cancer as the body tries to survive the insult. The ultimate answer is to find the offending antigens, treat the concurrent infection, while cleaning up the area of puss and discharge. Anti-inflammatory herbal preparations are administered and the overall health is improved with non offending, healthy, good nutrient-rich food. Inflammation is controlled and allergies are eliminated. It sometimes take months to gradually turn this mess back to peace and health, but it is possible short of ear ablation and surgery.
We have some ear ointments that I favor and some we have modified. The instructions on the containers often recommend the legal minimum that would do the job, recommending a few drops in a whole German shepherd ear. The amount recommended would not even come close to coating the skin of the ear canal much less being therapeutic. I recommend squirts, not drops. Most of the solutions that leave our clinic I modify to make more cleaning or increase the amount of antibiotic to double or triple the amount from the manufacturer. We have had great success with our A.C.C.E. Healing Gel in infected ears with antibiotic resistance. Many clients have preferred it over commercial products.