Accuracy of freehand versus dynamic computer-assisted zygomatic implant placement: An in-vitro study.

Objective: To compare the accuracy of zygomatic implant placement using a dynamic computer-assisted implant surgery system (D-CAIS) versus the traditional freehand approach.

Methods: An experimental in vitro study was conducted using 10 stereolithographic models randomized to two groups: D-CAIS (test group) and freehand placement (control group). A single zygomatic implant was placed on each side of the models. The accuracy of implant placement was assessed by superimposing the actual postoperative implant position, obtained via cone-beam computed tomography (CBCT), with the virtual preoperative surgical plan from the preoperative CBCT. Additionally, the operated side and surgery duration were recorded. Descriptive statistics and bivariate analyses were performed to evaluate the data.

Results: The D-CAIS group demonstrated significantly greater accuracy across most outcome variables. Reductions in angular (MD = -5.33°; 95 %CI: -7.37 to -3.29; p < 0.001), coronal global (MD = -2.26 mm; 95 %CI: -2.97 to -1.55; p < 0.001), coronal horizontal 2D (MD = -1.96 mm; 95 %CI: -2.60 to -1.32; p < 0.001) and apical global deviations (MD = -3.37 mm; 95 %CI: -4.36 to -2.38; p < 0.001) were observed. Accuracy in the freehand group varied significantly between operated sides. However, the surgical procedures in the D-CAIS group were significantly longer (MD = 11.90 mins; 95 %CI: 9.37 to 14.44; p < 0.001).

Conclusions: D-CAIS navigation systems offer significantly greater accuracy in zygomatic implant placement compared to the traditional freehand technique. Additionally, D-CAIS systems may minimize discrepancies in accuracy between operated sides, though their use is associated with an increase in the duration of surgery.

Clinical Significance: D-CAIS navigation systems improve the accuracy of zygomatic implant placement. However, an increase in the duration of surgery is to be expected.