Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 15 years of experience. I look forward to working with you.
Oh, I am so very sad to hear your dog has this. This can be fixed, but it may require a veterinary dentist to perform the surgery. Sometimes they can be really tricky to repair, and it sound like this is the case. As long as the hole is present, there is going to be odor and infection. There is not much that can be done other than surgery to repair/close the hole. I wish I could say I think the gel will help, but it probably will not. Oral antibiotics as prescribed by your veterinarian will help control infection, possibly reduce nasal discharge and reduce odor, though. This might buy you time to get a referral to your closest veterinary dentist.
Here is a wonderful link on the American Veterinary Dental society page that discusses the next step surgery (and this is a tricky surgery which sounds like your vet cannot do this; referral to a dentist is needed; let me reassure you this CAN be repaired; I've seen awful fistulas that are fixed) when the first flap repair fails: http://www.avds-online.org/info/oralnasalfistula.html
You do not need an official referral to see a veterinary dentist. If you want to search your area for a dentist here's one place to do a search:AVDC Dentist Directory or Vet dentists
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