To find out the reason we need post operative x-ray.The possible reason for the sensitivity are- 1)might the adjacent teeth have deep cavity. At the time of treatment doctor has done filling depending on clinical situation. But now the tooth have developed symptoms and started filling sensitivity. 2) Gums surrounding the tooth is inflamed and causing sensitivity. 3) The less likely cause will be the root canal treated has extra canal and causing sensitivity. if this is the cause than need to reevaluate the root canal treatment. You can visit your dentist and check with above possible reason.
