Firstly, it is not unusual for the tooth to be sensitive to hot and cold after a filling is placed. This does not necessarily signal the need for root canal therapy. If the filling was deep then the possibility for rct is present. I would allow the symptoms and the duration of such to determine the need for further treatment.Nitrous oxide does give you a state of euphoria which might help in getting the injection but if the anesthesia is not effective it really doesn't matter whetheryou had the nitrous or not. I would try to relax and see if the novocaine will be effective this time. I am guessing that it is a lower tooth and they are sometimes difficult to anesthesized.
sensitivity happens sometimes, especially with white (composite) fillings. if it is not deep, i personally would want to try a silver amalgam filling with a medicated base before having root canal treatment, which usually also means a crown. silver fillings dont cause nearly the same sensitivity issues as composites. Nitrous oxide indeed should help the nervousness. I would imagine you are talking about a lower tooth perhaps towrds the back which are harder to anesthetize.... the dentist probably just "missed the nerve" it happens.
it is a white filling. it is a deep cavity- she said she was worried about it. but i was good for 2 weeks following the filling, but now it is sensitive. who knows. thanks for the info.
if all the decay is gone, i'd still think about replacing it with an amalgam with a medicated base.
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