Understanding Predictability Error in Orthognathic Surgery

Introduction Orthognathic surgery aims to improve the facial aesthetics while maintaining stable jaw form and function. Lateral cephalometry provides objective data used in pre-op mock surgery to predict movement of the maxilla and mandible during orthognathic procedures. Patient and Methods A prospective cohort study was conducted on 30 adult orthognathic surgery patients. Mock jaw surgery predicted two-dimensional (horizontal and vertical) linear movement of maxilla and mandible. Operative procedures performed were bilateral sagittal split osteotomy and Le Fort I osteotomy. Seven-day pre-op cephalogram (T1) was compared to 7th day post-op cephalogram (T2) to assess hard tissue movement of point A (maxilla) and point B (mandible) using Cartesian ( X – Y ) plane. Results The difference between predicted values to the 7th day post-op outcome results was statistically insignificant ( p value less than 0.001). Conclusion Planning in orthognathic surgery using digitized two-dimensional cephalometric tracings and mock jaw surgery produces predictable results.