Surgical prediction reliability: a comparison of two computer software systems.

The purpose of this study was to test and compare the accuracy and reliability of soft tissue profile predictions generated from two computer software programs. The presurgical and postsurgical cephalometric radiographs of 28 patients were digitized onto each computer program. A customized analysis was created to determine the amount of surgical movement, as well as to compare the actual postsurgical soft tissue profile with the computer-generated prediction. The results demonstrated that, on the average, the predictions were not significantly different from the actual postsurgical profile changes. While each program generated statistically similar prediction results, marked variability was noted. There was no significant difference found in the prediction errors between patients who had one-jaw surgery and those who had two-jaw surgery. This study found that a linear relationship existed between the surgical movement and the prediction error. In general, the greater the magnitude of the surgical movement, the larger the prediction error.