The Research Of The Soft Tissue Of Skeletal â…¢ Before And After Orthognathic Surgery And The Prediction Accuracy Of The Computer Software

Objective:1.To evaluate the changes of the soft tissue in the occlusal deformity patients before and after orthognathic surgery, using the Surgicase CMF software.2.Conduct soft tissue computer simulation and prediction by Surgicase CMF software in skeletal class III malocclusion patients.Evaluate the prediction accuracy by three-dimensional overlapping and measurement,through the difference between the simulation soft tissue and the nature postsurgical soft tissue.Methods:1.A total of 25 consecutive class â…¢ patients in Stomatological Hospital of Nankai University were included in this study. All the patients underwent a CBCT(Implagraphy,vatech, Korea)examination within 7 days before and 6 month or more than 6 month after orthognathic surgery. Import the CBCT data into the Surgicase CMF software for soft and bone tissue reconstruction. And establish the related measurement system to carry on detailed statistical analysis simultaneously. The paired t test(SPSS 20) were used to statistical analysis and the test level of alpha =0.05.2.Take advangage of the Surgicase CMF software to simulate the orthognathic surgery,and obtain the simulation image. And analysis the difference of the simulation and the actual image by means of the measurement parameters. According to the color scale,calculate the accuracy of the Surgicase CMF software.Results:In the 11 measurement items:1.The soft tissue change before and after surgery in the patients with skeletal class â…¢malocclusion:enL-enR,Prn-Co,Sn-Me,with no statistically significant,indicating that the inner canthus has no significant change before and after surgery. The other items all hasstatistically significant in which G-prn-Pg, UI-EP, Sn-UI, Cm-Sn-UI measurements are in creased and Ls-ChL-ChR, ChL-ChR, AcR-AcL, LI-EP measurements are reduced.2.The prediction accuracy results: In the comparison of the simulated and the actual measurements, only the angle between the nose and lip and the width of the nose are stat istically significant, indicating that the prediction results differ from the actual surgery. T he Surgicase CMF software cannot predict the changes in the angle of the nose and lips a nd the nose width accurately. The other items are all no statistically significant, showing higher prediction accuracy of the other projects.3.Based on the comparison of hard and soft tissue overlapping,we observed that the prediction of most positions of soft tissue is accurate except the lip and nasal tissue.Conclusions:1.The facial expression of skeletal class â…¢ malocclusion can be corrected by orthognathic surgery. The occlusion and the facial expression can be changed and the performance of facial soft tissue tends to be normal.2.Surgicase CMF software can predict the bone tissue and most of the soft tissue of skeletal class â…¢ malocclusion accurately, but accuracy of the lip and nose width are low,it is need to improved.