Hi Geeta Rani, I think the problem that you are encountering is due to excessive reduction of the supporting teeth or abutments as we call them. The sensitivity may also be due to improper sealing of the bridge. Otherwise there is no reason that sensitivity should occur after a bridge fixation. If pulp canals have been exposed during the tooth reduction procedure, you will require a root canal treatment
for the supporting teeth and get refixation of the bridge done. So please get an X-ray done and consult your dentist
again or take a second opinion
from another dentist. Take care!