Objective: To compare implant accuracy of combined static and dynamic (SD) computer-assisted implant surgery (CAIS) with static (S), dynamic (D) CAIS, and freehand surgery (FH) for single implant placement. Materials and Methods:One hundred and twenty patients were randomized into four groups. Implants were placed using both stereolithographic surgical guide and dynamic navigation in the SD group, stereolithographic surgical guide in S group, dynamic navigation in D group, and conventional freehand in FH group. Analysis of deviation between planned and final implant position, as well as K means analysis was conducted for implant deviation at platform, apex, and angle (primary outcomes) and directional distribution at platform and apex (secondary outcome).Results: Significant differences were found among the four groups (p < .001): The 3D deviation at the platform (mm) of SD,