This case report presents the cases of single anterior missing and posterior free-end edentulous ridge
with computer-guided implant placement on the day of visit through a special tray containing
fiducial markers without model scan or intraoral scan data. Cone beam CT was taken after fixing
the marker embedded ready-made tray with a photopolymerized resin material by light-curing in
the patient's mouth. The implant location was planned on the registered CT data in the planning
software. The tool path calculation for the milling machine was conducted in the computer-aided
manufacture (CAM) software. The guide was completed by milling the drill hole in the special tray
as designed. Although the preparation for the conventional implant guide surgery takes considerable
time, including data acquisition and 3D printing, it was possible to produce a guide on the day of
the patient visit without a separate procedure other than a CT scan through this protocol. Also, the
transfer of the implant surgery plan, the process of scanning and 3D printing, was omitted, thereby
reducing the positional error between the CT data and the actual guide.