| Through the experiments of the facial soft tissue of skeletal class III patients before and after the change of the 3D scan and measure,facial bone tissue were examined by CT scan and measure the law department,facial hard tissue changes before and after the operation analysis,analysis of design and operation type behind to help surgeons in preoperative surgical plan also predicted for communication between doctors and patients.Objective:This study aims to analyze the change of facial soft tissue before and after surgery,the size of the qualitative and quantitative study of soft and hard tissues before and after operation,and further analyzes the correlation between soft and hard tissue changes,so as to guide the clinical orthognathic surgery plan and predict postoperative facial type.Method:Experiment 1.: by collecting 30 cases of skeletal class III patients with postoperative cranial CT and facial soft tissue 3D scan data fusion registration in mimics19.0 and ProplanCMF3.0 software,the establishment of space under the Cartesian coordinate system based on facial cranial jaw teeth 3D fusion model.Experiment two: 2.in the ProplanCMF3.0 software of 3D head model before and after surgery to determine the 18 anatomic landmarks were measured before and after surgery,the anatomical landmark coordinates,and the coordinates of X,Y and Z respectively in the direction of the difference,the difference data t test,P< test standard 0.05,analysis of the anatomical landmarks of facial hard tissue changes.Experiment three: 3.in the ProplanCMF3.0 software of preoperative and postoperative 3D facial model to determine the 20 anatomic landmarks were measured before and after surgery,the anatomical landmark coordinates,and the coordinates of X,Y and Z respectively in the direction of the difference,the difference data t test,standard P< 0.05 test,analysis of anatomic landmarks of facial soft tissue changes.4.Experiment four: experiment two and three of the soft and hard tissue landmarks will coordinate data matching,soft tissue landmarks change data of Pearson test,make a scatter diagram,correlation analysis of various markers of hard tissue changes,and analysis of the marking points of soft and hard tissue change ratio.Result:1,experiment: 1)through the CT scan of the head and face like a 3D scan for preoperative and postoperative 6 month head CT data and 3D face data.2)the 3D head model and facial skin soft tissue model STL format 3)by Frankfurt plane calibration based on standard head position and space coordinate system of orthognathic surgery design.4)will T0 3D fusion and CT facial reconstruction of facial skin and soft tissue data registration,it is found that the two is not evenly,and facial soft tissue profile in bilateral cheek than CT scan reconstruction to obtain more full.Experiment two: 2.to 18 3D before and after surgery on the skull model for hard tissue anatomy study found that change of coordinates,but had no significant changes in the level of mandible;sagittal maxillary advancement changes significantly,the average 2-3mm,the average lower back 5-6mm,slightly more than the amount of mandibular setback is 2 times the amount of maxillary anterior migration;vertical jaw occurred significantly raised.Experiment three: 3.adult skeletal Class III malocclusion patients with facial soft tissue change quantitative study showed that: the preoperative and postoperative 3D image of the face of the same coordinate registration after the fusion of qualitative research before and after the surgery of facial soft tissue changes in regional levels and comparison analysis showed that: 1)the maxillary orthognathic osteotomy advancement surgery LeFortI after the change of the soft tissue region is the nose on both sides and the upper lip area,ranging from the lower level to the outer canthus of nasal bone,vertical,down to the mouth and upper lip vermilion bilateral connection area,and the range of soft tissue changes in forward inequality,the trend is gradually reduced from top to bottom,to both sides of the soft tissue forward from the middle.2)BSSRO mandibular osteotomy back after the surgery,the lower lip to the submental area,both sides to the mental foramen,the range of soft tissue are back,and withdrawal of the mentolabial sulcus region,the central region of the lower lip vermilion,diffusion of soft tissue along the two area to the surrounding back gradually decline.3)class III patients treatdedby bimaxillary surgery,the variation of mandibular region soft tissue than maxillary region,bilateral mandibular angle region is posterior width did not change,4)bimaxillary surgery facial height were shorter overall.The Research Triangle upper lip nasal base,maxillary leFortI osteotomy advancement mandible bilateral sagittal split ramus osteotomy back after surgery,nasal columella average short upper lip height 0.51 mm,variable length 0.71 mm,the tip of the nose upper lip longer distance of 1.39 mm,illustrate the nasolabial angle change,nose to nose point shorter 0.74mm/0.95 mm,that nose to both sides bulging,alar width 1.38 mm.4.Experiment four: the relationship between soft and hard tissue changes that there is no linear correlation between the hard and soft tissues changes,while the linear mandibular soft and hard tissue changes,and the changes of soft and hard tissues is significantly lower proportion of maxillary mandibular.At the same time,the author tries to use the hard and soft tissue changes in the proportion of analysis of orthodontic orthodontic and orthognathic treatment in decompensation before surgery to reverse jaw distance,as a preliminary judgment to increase the anti jaw tooth when compensatory and not a factor.Conclusion:Changes in facial tissue before and after III surgery mainly for the maxillary bone becomes full,especially surrounding the nose upper lip area,bilateral buccal mandibular setback significantly widened;mainly for mandibular symphysis,bilateral mandibular angle region was significantly widened;alar width,upper lip was longer.The correlation between soft and hard tissue of mandibular than maxillary,mandibular chin soft and hard tissue changes close to linear correlation.The proportion of soft and hard tissue changes can provide guidance to the operation design,provide guidance for prediction of back type. |
