I have had excellent results using a topical solution made up by putting 10 ml of 5% sodium chlorite in a glass, adding 10 ml of 10% citric acid , activating for 10 minutes, and then diluting with water to make a total of 500 ml. I use this around the house, and spray it on cuts, scrapes, and puncture wounds. This is what we poured into Rico's ears.
Enough solution was poured into the ear canal to fill it. Rico's head was held on its side and the base of the ear was massaged to work it in. The hold time was one minute. Then Rico shook his head to clear it and we moved on to the other ear. The other ear was given the same treatment. This treatment was done in the morning and at night.
The oral solution was the difficult one to figure out. We ended up putting 1 ml of 5% sodium chlorite in a glass, adding 1 ml of 10% citric acid , letting the activation continue for 10 minutes, and then diluting with 1 liter of water. This ended up with a solution that with a concentration just over 1 PPM free chlorine dioxide. I started with a solution that was stronger, but we had to cut back to get Rico to accept it. According to the studies done with rats, Rico, at 93 pounds, was not in danger of ingesting too much chlorite or chlorine dioxide with a solution of this strength.
Things happened so fast that we didn't get around to using the mouthwash, but further study indicates that it probably wouldn't be effective in a dogs mouth. I believe a dogs mouth has a higher PH than a humans, and I am not sure if the biofilm on the teeth would have enough acid to activate the sodium chlorite in the mouthwash during brushing. I am thinking that we will use the same solution we used for the oral treatment.
There are some commercial products available for tooth care with dogs, but I haven't run across any studies showing the efficacy of these products. I have lined up several dog owners that have dogs that end up with tarter on their teeth, so maybe we will conduct our own test.