There seems to be some discussion about whether this is odontoma OR an infection of some type? It certainly does not have to be one or the other, it probably is both. The x-rays show what looks like a classic case of odontoma (almost diagnostic) and the presence of an "awful" smell as a tooth falls out is suggestive of an anaerobic infection. Odontoma often leads to infection due to the calcified mass pushing into soft tissue. I'll just second STS's recommendation for Clavamox, it will probably be more effective in this situation. Good luck with Rocky, I hope you can get a good outcome for your little guy!