Comparison of implant placement with optical position system and free-hand approach

The aim of this study was to compare the deviations of planned and placed implants placed by the assistance of a micron tracker-based dynamic navigation device or freehand methods. 32 patients with bi‐lateral teeth loss in the posterior maxilla were included. A thermoplastic fiducial marker was adapted for the remaining teeth, and cone‐beam computerized tomography was used for imaging. A minimum of one implant was planned for each side of the maxilla, and the dynamic navigation device or freehand method was randomly used for surgical insertion. Deviations were measured by matching the planning data with a final CBCT image. The results were analysed by generalized linear mixed models (P < 0.05). A total of 92 implants were placed uneventfully, and 86 implants were included in the final analysis. In the NAV and FRE groups, the mean linear deviations in the shoulder of the implants were 1.01 mm (SD: 0.07) and 1.70 mm (SD: 0.13) (P < 0.001), mean deviations in the tip of the implants were 1.83 mm (SD: 0.12) and 2.51 mm (SD: 0.21) (P < 0.001), and mean angular deviations were 10.04° (SD: 0.83) and 5.59° (SD: 0.39) (P < 0.001), respectively. No learning curve was revealed. Compared with the FRE group, approximate 33.83% and 79.60% reductions for the respective linear and angular deviations were achieved in the NAV group. The NAV technique can be used to transfer virtual implant planning to the patient's jaw with increased accuracy.