Thanks for putting up your question on Just Answer.
To answer your first query, a prolonged period before root canals is NOT indicative of a prolonged healing period.
Regardless of the degree of pain, a root canal should take away all the sensation from that tooth.
Secondly, your fears may be true. The broken tooth may have now reached the stage where a root canal is what is needed.
However, pain after root canals is not uncommon, and can occur due to any or a combination of the following reasons:
1. Over instrumentation during the root canal cleaning
procedure (going beyond the root canals)
2. Forceful irrigation ( injecting the irrigant solution which pushes it past the root canals)
3. Contact of opposing tooth on the tooth being treated between appointments (ideally there should be no contact even on biting until the crown is placed)
4. Inadequate instrumentation (some amount of pulp
tissue is still left,which when touched causes pain)
5. An entire root canal missed (not picked up on an X ray),and thus not cleaned
6. A broken instrument being left inside the root canal
I suggest you return to your dentist without further delay and ascertain the cause of the pain.
Hope this answers your question. Feel free to contact me again for more information.
I wish you a speedy recovery !!!
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