I have had ongoing sinus infections for years it seems. In July, my left-side K-9 tooth began to ache. After the pain had become too much to bare & my face began to swell, I went to a after hours clinic where I was given antibiotics for a sinus infection. Once I finished them, the pain began in my tooth again, then the swelling and so on... I finally went to a dentist in December who said I needed a root canal on that k-9 tooth. I went to another dentist for a second opinion, who also confirmed that I did indeed need the root canal. I had the root canal done just last Monday and now the other k-9 tooth is beginning to ache just as the previous k-9 had... Can this all be due to the ongoing sinus infections? Could there be some sort of way that the infections in the sinsuses is getting in to the teeth? I fear that I am about to go through the exact same thing with this other k-9 tooth and wonder if I should see an Ear, Nose & Throat specialist before I have to have another root canal!!!!