I had a root canal on a tooth over a year ago and now I am having pain all on the right side of my face and I can't chew. I saw a dentist and got antibiotics and pain meds and now they are telling me I might need to have another root canal. How does a root canaled tooth get infected? Now I am going to have to pay to have the same procedure redone not to mention the cost of another crown. Are there any other options besides another root canal or extraction?