Removal of maxillary wisdom teeth stumps is difficult because the stumps are not easy to hold and are fragile and friable, in addition, the stumps may enter the maxillary sinus during the extraction process, causing perforation of the sinus floor, as follows. 1. The residual root is not easy to hold and fragile: high residual root can be extracted with root forceps, and low residual root can be extracted with root tapper, due to the deeper position of wisdom teeth, it is inconvenient to operate the instruments to increase the difficulty of extraction. At the same time, wisdom tooth stumps are usually carious, fragile and friable, and may leave broken pieces of tooth during extraction, which need to be carefully explored and removed. 2. The residual root may enter the maxillary sinus: some wisdom teeth roots are closer to the bottom of the maxillary sinus, the residual root may enter the maxillary sinus during extraction, which needs to be taken out by flap debridement method, and at the same time the perforation of the bottom of the maxillary sinus will be dealt with by surgical treatment. It is recommended to go to a regular medical institution to receive professional treatment.