Hi..
Welcome to HEALTHCARE MAGIC..
I have gone through your query and can understand your concern...
As per your complain in case if the tooth was capped after
root canal treatment then it is possible that there is re-infection in the tooth and the pain is due to it as the pus might have formed below the root tips causing pressure over the nerves and is really painful..
In this case removal of the cap under local anaesthesia and re-doing of root canal treatment and placing cap again has to be done..
Other condition can be that there is some left out root canal that is missed during treatment and the nerve tissue in it is getting inflamed leading to pain..
Re-exploration of the canal and cleaning and filling of the same is the right treatment..
In case if the tooth was not treated with root canal and directly cap was placed then there is possibility that the nerves have got exposed at some point over the tooth leading to inflammation of the nerves and pain..
In this condition also cap needs to be removed and root canal should be done..
Consult a Pedodontist and get him evaluated..
Hope this information helps..
Thanks and regards..
Dr.Honey Nandwani Arora..