Accuracy of face-bow transfer: effect on surgical prediction and postsurgical result

One of the most common errors in model surgery for orthognathic surgery is in the mounting of the models on the articulator. This study assessed the ability of one type of face-bow to transfer the maxillary model to the articulator. Twenty-five consecutive mountings were evaluated by calculating the angle made between the maxillary occlusal plane on the cephalogram and comparing it with the maxillary occlusal plane angle on the articulator. An accurate face-bow transfer should transfer this angle, making the two similar. It was found that a significant difference between the maxillary occlusal plane angle on the cephalogram and the articulator was found in the average case. The implications of such errors and a technique to avoid them are presented.