RESUMEN
Objective:To establish a computer-aided design and 3D printing system for precise implantation of micro implant anchorage, and accurately calibrate the position and direction of micro implant implantation.Methods:A retrospective selection was conducted on 15 patients (30 in total) who underwent micro implant implantation surgery from the Department of Stomatology, the Affiliated Hospital of Jiangnan University from November 2019 to November 2021, including 6 males and 9 females, aged (17.1±6.3)years old. The preoperative patient was photographed with cone beam computed tomography (CBCT) and the collected DICOM data format was output. A 3D scan was performed on the patient′s preoperative analysis model to obtain the STL file of the model scan. The CBCT data and model data were fitted and matched using 3Shape Implant Studio software, and the thickness of the guide plate, the amount of undercut compensation, and the size of the key component collar were designed. The 3D printer was used for printing after resizing. Using the assist method to implant micro implants, CBCT was taken postoperatively to compare the preoperative design with the postoperative results.Results:After fitting the postoperative CBCT with the designed CBCT of the micro implant, it was found that the micro implant was consistent with the preoperative design, maintained a safe distance and parallel to the adjacent tooth root, and did not damage the maxillary sinus and other areas. No detachment of the micro implant anchorage was observed 1 or 3 months after surgery. The application of assisted micro implant anchorage 3D guide plate was reliable, with accurate implantation position and direction, and can be implanted in most parts of the oral cavity.Conclusions:The use of computer-aided design and 3D printing system to create an assistive micro implant anchorage 3D guide plate can accurately locate the position and direction of the micro implant, which is worthy of clinical promotion and application.
RESUMEN
OBJECTIVE@#To compare accuracy of anterior cervical pedicle screws between assist of rapid prototyping 3D guide plate and free-hand insertion, and evaluate the safety of two methods.@*METHODS@#Eight adult cervical cadaver specimens after formaldehyde immersion, including 4 males and 4 females, aged 32 to 65(40.3±5.6) years old. After X-ray examination to exclude bone damage and deformity, 4 of them (3D guide plate group) randomly selected were for CT scan to obtain DICOM format data, and the data was imported into Mimics software for model, designed the ideal entry point and nail path for anterior cervicaltranspedicular screw (ATPS). After obtaining the personalized guide plate of the nail channel, it was exported as STL data, and the individual guide plate was printed by rapid prototyping and 3D printing technology. In turn, with the assistance of 3D guide plates, one-to-one personalized ATPS screws were placed on the four lower cervical cadaver specimens. Another 4 (free-hand group) lower cervical cadaver specimens were implanted with ATPS screws using free-hand technique. All specimens were performed CT thin-layer scanning and three-dimensional reconstruction after operation. The Tomasino method was used to evaluate the safety of the screws on the CT cross-sectional and sagittal images, to determine whether there was a cortical puncture of the lower and inner edges of the pedicle. According to the CT rating results, gradeⅠandⅡwere safe, and grade Ⅲ- Ⅴ were dangerous.And the accuracy of screws was recorded and analyzed between two groups.@*RESULTS@#Two screws were inserted in each segment from C@*CONCLUSION@#The 3D printing rapid prototyping guide plate assisted insertion of the anterior cervical pedicle screw can significantly improve the accuracy and safety, and provide a theoretical basis for further clinical application.