After root canal treatment, for teeth with large defects, without the nutrition of the pulp tissue, their own brittleness increases and the support force is relatively weakened, so it is necessary to do crown piling after root canal treatment, i.e., adding a very elastic fiber pile in the root canal system to help the root support the socket, making the socket more stable, better support, and better restore the normal function of the tooth. Some patients may fear that staking will be painful. In fact, after root canal treatment, the root canal system is filled with fillings, no pulp tissue or nerve, so there is no pain when staking inside.