2 Cases of Navigation Surgery for Genioplasty

Abstract

We report two cases of genioplasty performed using a navigation system. In recent years, virtual orthognathic surgeries have been performed using simulation software with data from preoperative computed tomography （CT）, and the osteotomy design, direction and distance of bony segment movement have been established. Despite the accuracy of simulations using three-dimensional CT data, results obtained from simulations cannot be effectively applied to clinical practice unless comparisons can be made to actual surgery. We report our experience of performing genioplasty using simulation software with preoperative CT data, and established the osteotomy design as well as the direction and distance of bony segment movement. Simulation-guided navigation osteotomy was performed with reference to simulation results transferred to the navigation system. A reference antenna was attached to the head of the patient using a headband. Next, interfacing laser registration was performed. Osteotomy was then performed along the osteotomy line drawn on the chin bone surface using piezosurgery and a tracker, and the bone segment was mobilized by down-fracture using a bone saw. Using the image of the simulated repositioned bone segment shown on the navigation system screen, the bone segment was moved to the determined position and fixed. Our results suggest that use of a navigation system allows safer, more precise genioplasty.