Purpose: To compare the linear and angular deviations of sites prepared for implants with the proposed 3D-printed sliding guide vs a 3D-printed conventional sleeveless static guide. Materials and Methods: This study consisted of two groups: a control group of 14 3D-printed conventional sleeveless static guides, and a test group of 37 3D-printed sliding guides. The guides were designed to drill 37 implant sites in each group. Linear and angular deviations were determined after scanning the drilled casts. Linear deviations were measured at the coronal and apical aspects of the drilled implant sites at 5-, 10-, 15-, and 20-mm distances. Results: There were no significant differences between the control and study groups regarding the coronal and 5-mm apical linear deviations. The angular and 10-, 15-, and 20-mm linear deviations of the 3D-printed sliding guide were significantly smaller than the control group. Conclusions: The proposed 3D-printed sliding guide could reduce the angular deviation of drilled implant sites from the planned positions, which is reflected in reducing the linear apical deviation of prepared implant sites longer than 5 mm.