Augmented Reality Navigation Versus Patient-Specific Cutting Guides for Simulated Fronto-Orbital Surface Trajectories in Facial Feminization Surgery: A Preclinical Accuracy Study

This preclinical investigation examined whether optical see-through augmented reality (AR) can transfer planned fronto-orbital cutting paths during simulated frontal debossing compared with patient-specific CAD/CAM cutting guides (CGs). Twenty printed skull replicas derived from one CT dataset were divided equally between workflows. Four superficial frontal or supraorbital grooves were created per skull and evaluated using postoperative CBCT and bidirectional closest-point distances. Overall deviation averaged the four trajectory means within each skull, giving 10 independent observations per group. Skull-level median [Q1, Q3] deviation was 0.543 [0.496, 0.588] mm with CGs and 1.098 [0.907, 1.333] mm with AR. Exact two-sided Mann–Whitney comparisons with Holm correction across overall accuracy, execution time, and four regions favored CGs for overall accuracy (adjusted p = 0.0208), superior frontal and right supraorbital accuracy, and execution time (adjusted p = 0.0029). The median [Q1, Q3] cumulative groove-execution time was 65.5 [61.5, 78.5] s with CGs and 152.0 [131.5, 208.8] s with AR. Mechanical guides deviated less with shorter groove-execution times in this standardized model, while operator and learning effects were not adjusted for. These findings concern surface trajectory reproduction in rigid models; clinical validation and assessment of the complete workflow are needed.