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Dentistry/Will a potential filling require another root canal?



I recently had a number of cavities filled, one of the teeth that was filled shortly after (#29) began to cause me extreme pain. I later learned after asking my dentist continuously during the next few appointments that the nerve in the tooth had died and a root canal was required. I was sent to an endodontist who that day performed the root canal and gave me a temporary filling. I returned a week later with an infection right below the same tooth on the root (probably from the bacteria that may have found it's way into my gum during the root canal procedure) This was also very painful and caused a great deal of discomfort. The endodontist completed the root canal and let the infection drain. I was put on stronger antibiotics (Clindamycin) and this seems to have cleared up my problem. This whole process lasted for about five weeks between getting the fillings and finally getting the root canal, dealing with the infection etc.
     I have three teeth on my bottom left side that still have to be filled. (#20) seems to have a very dark almost black looking decay and I am really afraid that this tooth may also require a root canal. Let me say that none of these three teeth are giving me pain, they are slightly more sensitive to hot and cold and I do have some level 2 pain there once in awhile but nothing really painful. I simply don't want to go through the process of getting it filled and then having the nerve die and having to get a root canal again. I am due to see the endodontist in a week to have a checkup on the tooth that was given a root canal. Would it be possible for them to do an x - ray and observe whether my tooth #20 is in need of a root canal? Like I said, I just don't want to have to go through this process again. My dentist did not check on the tooth last time after I had told him I had serious pain there so I'm not sure I completely trust him to make the proper diagnosis this time. Forgive me for being skeptical, I'm sure he was just doing his job but I am a full time student and am an hour and a half away from my dentist.

Hi Caleb,
Sorry for your recent dental issues.  I know it's frustrating when a tooth has work on it and then needs a root canal.  It does not mean that every filling will turn into a root canal.  It depends on how deep the decay is, how close it is to the nerve, and how your nerve responds.  Often time, the nerve can heal and adapt to having the filling/procedure done on the outer aspect of the tooth.  Sometimes, the nerve goes the opposite direction leading to pain as the nerve is dying and that space gets infected.

After a filling or crown on the outer aspect of the tooth, you can expect the tooth to be hypersensitive to hot/cold for 2-4 weeks, sometimes up to 6 weeks. That sensitivity should improve over that time period.

Hope this helps,

KG Amin, DMD

Austin Center for Endodontics (Root Canal Specialists)
Austin Center for Endodontics  


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Ketan Amin, DMD


Graduating from Harvard School of Dental Medicine, I received a broad understanding of both medicine and dentistry. I continued my training at New York University, as a dental specialist in endodontics, which concerns root canal therapy, related surgeries, as well as diagnosing and managing various forms of pain occurring in the head and neck


Dentistry; Specialist in Endodontics (Root Canal Therapy).

American Association of Endodontics American Dental Association American Academy of OroFacial Pain

Harvard School of Dental Medicine-Doctorate in Dental Medicine (DMD) New York University College of Dentistry-Certificate, Endodontics

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