Crowns that require pile restorations are also called pile crown restorations, and the timing of pile crown restorations depends on the tooth that is being braced. If the tooth is defective due to decay and other reasons, or if the trauma makes the remaining tooth too short or too weak to be repaired directly, it is necessary to drive a pile in the root of the tooth to reinforce and extend the crown of the bad tooth so that the denture gets enough strength to be fixed. The conditions of teeth that need staking are mainly divided into the following: 1, those with large crown loss due to decay or trauma; 2, those with tooth loss with only usable residual roots, healthy gums and periodontium, roots with sufficient length and dentin shoulder collar of more than two millimeters; 3, teeth that are misaligned, twisted and not eligible for orthodontic treatment or are non-orthodontic indications; 4, malocclusion, too small teeth or poorly retained 4. teeth that are malformed, too small or poorly retained.