A surgical stent is essential for the correct placement of implants during surgery. The optimal positioning of implants facilitates the fabrication of prostheses, and achieves a better prognosis. However, even with a surgical stent, the implant placement is not always as intended. To eliminate such discrepancies, we describe a technique to fabricate an assistant guide to help surgeons evaluate the parallelism and inclination between each drill bit, and the predetermined direction during implant surgery.