Abstract: Objective: To evaluate the application effect of digital fence type miniscrew guide plate manufactured by chair side design and 3D printing in implantation surgery of miniscrew. Methods: Fifteen patients who require miniscrew implantation were selected. Cone beam computed tomography (CBCT) of oral and maxillofacial regions was taken before surgery. Digital intraoral scanners were used to obtain oral scan images, and 3Shape Dental System software was used to fit the two images before designing a guide ring. The guide ring file and oral scan image were imported into Plasty CAD software to complete the design of the fence type guide plate. Chair side 3D printing equipment was used to print the guide plate. The plate was polished and trial worn after light curing. Thirty miniscrews were implanted under the guidance of the guide plate. Postoperative CBCT images were taken after surgery and aligned with preoperative CBCT images. The deviation, including angle deviation and position deviation, between the actual implantation and designed implantation was measured to analyze the accuracy. The minimum distance between the actual implanted miniscrew and the natural tooth root was measured to evaluate the safety of implantation. The fixation of miniscrews within 3 months after implantation was observed and the stability was evaluated. Results: The angle deviation between the actual implantation and the designed implantation of the miniscrews guided by the digital fence guide plate was (1.25±3.41)°, and the deviation values between the actual implantation and designed implantation of miniscrews in the neck and root positions were (0.17±0.46) mm and (0.13±0.41) mm, respectively. There was no statistically significant difference (P＞0.05). Thirty miniscrews did not contact with the root of the tooth, with safety level Ⅰ accounting for 86.67% and level Ⅱ accounting for 13.33%. There were no cases of level Ⅲ. Within 3 months after surgery, there was no loosening of the miniscrews, and the stability rate was 100%. Conclusion: The digital fence type miniscrew guide plate can effectively improve the accuracy, safety, and stability of implantation. The chair side design and 3D printing production method are convenient and reliable, which shortens the treatment cycle and has important application value.

Key words: fence type, miniscrew, guide plate, chair side design, 3D printing