Abstract: Objective： According to explore the causes and treatment of mechanical complications in dental im- plant surgery. Methods： 8 cases of dental implant complications occurred in longgang central hospital, in- cluding 5 cases where the central screw rod of the implant carrier was broken and 3 cases where the base screw was broken when the implant was implanted for immediate repair were collected. According to dif- ferent implant systems and different mechanical complications, corresponding treatment schemes were im- plemented. Result: 7 cases of central screw rod and base screw of the device were completely removed. The postoperative prognosis was good, the implant was not loose, and the subjective satisfaction of the pa- tients was good after the repair. 1 case replanted after the implant was removed, 6 months after the final restorationand were satisfied. Conclusion： Preoperative examination and analysis not only minimize the complications of implantation repair but also improve the success rate of implantation surgery.

Key words: dental implant, mechanical complication, prevention and treatment, broken