Effects of supporting conditions and anchor microscrew on the stabilization of the implant guide template during the drilling process: An in vitro study

Statement of problem: Implant placement errors have been reported in guided surgeries because of movement of the guide template during implant placement. With a completely limiting guide design with high restrictions, guide template stabilization is essential to minimize mobility during the drilling process. Purpose: The purpose of this in vitro study was to evaluate the effects of supporting conditions and the use of an anchor microscrew on the seating and functional stabilization of a computer-aided design and computer-aided manufacturing (CAD-CAM) implant surgical guide with a completely limiting design. Material and methods: Twelve implant surgical guide templates were fabricated under different supporting conditions: tooth-mucosa, tooth-tooth, tooth-screw, and screw-screw (n=3 per group). In the tooth-screw and screw-screw groups, anchor microscrews and anchor caps were used to fix the guide templates. The seating stability of the templates was evaluated by using a micromovement assessment. The functional stability of the templates was analyzed during the drilling process by using a motion tracking method. One-way analysis of variance and the Tukey HSD post hoc test were conducted to compare the differences among the groups (α=.05). Results: The tooth-tooth, tooth-screw, and screw-screw groups exhibited similar seating stability, which was significantly more stable than that of the tooth-mucosa group (P<.001). In terms of functional stability, the tooth-mucosa group reported the highest positional deviation and motion magnitude, whereas low values were found in the tooth-screw and screw-screw groups (P<.001). Conclusions: The use of anchor microscrews can increase the seating and functional stability of CAD-CAM guide templates during the drilling process for implant placement.