Accuracy analysis
After the implant was placed, postoperative CBCT was performed using the same parameters. The accuracy was analyzed by a open-source software 3D Slicer (Version 4.13, Harvard, Boston, USA, 
Fusion and calibration of preoperative and postoperative images by 3D Slicer
Illustration of deviations (platform, apex and angulation) of implants between pre-operation design and actual post-operation placement