Hi.. Thanks for the query.. Numbness and tingling of the teeth gum and chin after a root canal procedure is done indicates that there is injury to the nerve.. iT is most commonly during the injection which causes pricking of the nerve leading to paresthesia of the nerve and feeling of numbness and tingling.. If it is due to overfilling of the root canals causing compression over the nerve fibres it means that the filling material has gone much beyond the root apex and the nerve cannot heal until the compression is removed.. In this case removal of the root canal filling from the respective canal which is over filled followed by refilling upto the desired length has to be done.. The nerve injury will slowly heal over the time but the time duration cannot be certain as it can take from days to weeks and even months and years for the nerve to heal.. Hope this helps.. Regards..