All I am finding is Jack's Canker powder that you put in the ear canal and that is not what I mean at all.
What I had was sent to me from England is Thornit canker powder and I was told to use it to keep problems from occuring again. I was told to sprinkle a tiny bit on the outside of the inner part of the ear....not the ear canal. I'm not sure if that helped or what my vet gave me but so good so far. I would not try it without checking with your vet first. This was the only thing I ever tried other than what my vet prescribed.
I can give you the site info that was on the little bottle she sent me.
www.doghealth.co.uk
This can be used for cats and rabbits too.