目的: 动态导航系统在种植外科中广泛应用，种植外科手术可以根据植入时机的不同分为即刻种植和延期种植。本回顾性研究的目的是比较动态导航下即刻种植与延期种植的精度，探讨即刻种植对动态导航下种植精度的影响。方法: 收集97例病例(男性53例，女性44例)，平均年龄(47.14±11.99)岁，共97枚种植体，其中51枚为延期种植，46枚为即刻种植。通过测量种植体植入三维位置与术前种植计划的偏差，对延期种植及即刻种植的精度进行定量对比评价。选择角度误差、植入点三维误差和根尖点三维误差作为主要观察指标，将植入点的水平误差、末端点的水平误差、植入点深度误差以及末端点深入误差作为次要观察指标。结果: 纳入的种植修复体的一年留存率和成功率均为100%，无机械或生物学并发症。整体植入点的三维误差为(1.146±0.458) mm，根尖点的三维误差为(1.276±0.526) mm，角度误差为3.022°±1.566°。延期种植组植入点的三维误差为(1.157±0.478) mm，根尖点的三维误差为(1.285±0.481) mm，角度误差为2.936°±1.470°；即刻种植组植入点的三维误差为(1.134±0.440) mm，根尖点的三维误差为(1.265±0.780) mm，角度误差为3.117°±1.677°，两组间差异均无统计学意义(P值分别为0.809、0.850、0.575)。结论: 动态导航下即刻种植的精度与延期种植相似，可以满足临床要求。

Objective: Dynamic navigation approaches are widely employed in the context of implant placement surgery. Implant surgery can be divided into immediate and delayed surgery according to the time of implantation. This retrospective study was developed to compare the accuracy of dynamic navigation system for immediate and delayed implantations. Methods: In the study, medical records from all patients that had undergone implant surgery between August 2019 and June 2021 in the First Clinical Division of the Peking University School and Hospital of Stomatology were retrospectively reviewed. There were 97 patients [53 males and 44 females, average age (47.14±11.99) years] and 97 implants (delayed group: 51; immediate group: 46) that met with study inclusion criteria and were included. Implant placement accuracy was measured by the superposition of the planned implant position in the preoperative cone beam computed tomography (CBCT) image and the actual implant position in the postoperative CBCT image. The 3-dimensional (3D) entry deviation (3D deviation in the coronal aspect of the alveolar ridge), 3D apex deviation (3D deviation in the apical area of the implant) and angular deviation were analyzed as the main observation index when comparing these two groups. The 2-dimensional (2D) horizontal deviation of the entry point and apex point, and the deviation of entry point depth and apex point depth were the secondary observation index. Results: The overall implant restoration survival rate was 100%, and no mechanical or biological complications were reported. The implantation success rate was 100%. The 3D entry deviation, 3D apex deviation and angular deviation of all analyzed implants were (1.146±0.458) mm, (1.276±0.526) mm, 3.022°±1.566°, respectively; while in the delayed group these respective values were (1.157±0.478) mm, (1.285±0.481) mm and 2.936°±1.470° as compared with (1.134±0.440) mm, (1.265±0.780) mm, 3.117°±1.677° in the immediate group. No significant differences (P=0.809, P=0.850, P=0.575) in accuracy were observed when comparing these two groups. Conclusion: Dynamic computer-assisted implant surgery system promotes accurate implantation, and both the immediate and delayed implantations exhibit similar levels of accuracy under dynamic navigation system that meets the clinical demands. Dynamic navigation system is feasible for immediate implantation.