Spatiotemporal Analysis of Molecular Continuity in Pathogenesis of Squamous Cell Carcinoma: From Normal Epithelium to Precancerous Lesions and Carcinoma.

Background and

Objectives

Virtual surgical planning (VSP) is well established in mandibular reconstruction. However, it is difficult to position bone segments precisely in the operating room due to a lack of visual control and deviating intraoperative conditions. Navigation can help to transfer surgical plans more precisely. We present a color-coded navigation based on electromagnetic tracking that provides simplified 3-dimensional (3D) visualization and real-time feedback to assist with precise bone segment positioning. The aim of this study is to evaluate our approach in model surgeries using 3D-printed bones.

Methods

We developed software for landmark-based registration and color-coded navigation. Prior to model surgeries, VSP was performed on 11 cases involving hemimandibular defects using in-house software. Osteosynthesis plates were prepared, and bone phantoms and cutting guides were 3D-printed. Mandibular reconstructions were then performed in a laboratory setting using our navigation software. To evaluate applicability and accuracy of our navigation, we compared anatomical and artificial landmarks on the graft via postoperative cone beam computed tomography.

Results

Navigated mandibular reconstructions were precise compared to VSP, with measured spatial differences of 2.16 ± 1.1 mm at artificial landmarks, 2.95 ± 1.59 mm at the condyle, 2.37 ± 1.4 mm at the jaw angle, and 1.13 ± 0.75 mm at the junction between graft and residual mandible. No substantial differences were found between navigation measurements and cone beam computed tomography.

Conclusions

Color-coded navigation with simplified 3D visualization of bone segments yielded promising results in model surgery. It has great potential to assist with precise bone segment positioning in mandibular reconstruction.