Three-dimensional Measurement And Classification Of Mental Deformity And It's Digital Diagnosis And Treatment

Objective1?Three-dimensional CT data were used to measure and analyze the spatial position of the chin in normal people.On this basis,criteria were developed to describe the spatial position of the normal chin,and the mental deformity was classified according to the abnormalities in the spatial position of the chin.2?The relevant indicators of patients in each category were measured,and the corresponding indicators of the normal population were compared and analyzed to explore the causes of the formation of each category of malformation.3?A precise diagnosis and treatment of mental deformity based on digital design and manufacturing technology was explored,including accurate diagnosis of mental deformity based on 3D CT reconstruction technology,virtual surgical simulation design based on multiple data fusion technology,and personalized production of mental osteotomy guide plate and positioning guide plate based on 3D printing technology.MethodsMeasurement of analyzing the characteristics of the general population and chin space position,on the basis of laying describe normal and chin spatial location,and press the space position of the mentum abnormalities,classifying and chin deformity,at the same time on the classification of patients with related indicators to measure,and corresponding index is compared with the normal population analysis,explore the reasons for the formation of the classification of deformity.Acquisition of DICOM format in patients with skull CT data,teeth model of laser 3 d scanning data and facial 3 d data of photography,using ProPlan CMF 3.0,Geomagic Studio 11 and Geomagic Design X craniofacial bone and soft tissue three-dimensional reconstruction,replacement teeth registration,multivariate data fusion,3 d coordinate measuring surgical landmark,virtual surgery and surgical results of bone cutting simulation,the precise intraoperative to bone mass and scope.The preoperative surgical design was transferred to the real surgery through the 3D printed jaw osteotomy guide plate and positioning guide plate.Head CT was taken postoperatively,preoperative design and postoperative CT registration were performed,and error was detected.Results:Normal values of related indicators in adult han females were:mental offset 1.290.76(mm);Mental projection-2.17 2.98(mm);Subsurface ratio 1.279 0.033;Lower edge level Angle difference of 0.667+/-0.540(°);Chin width 29.7 3.98(mm).The distance between Po and N point and perpendicular to the vertical line of FH and the ANS-Me/N-ANS ratio can well reflect the spatial position of the chin,and the difference between the chin distance and the angle between Go-Gn line and the FH plane can well reflect the chin asymmetry.The mental osteotomy program predicted by 3D CT was consistent with the simulated program.The mental osteotomy guide plate and positioning guide plate made by the above method were closely adhered to the lower dentition and mental bone surface during the operation,and were successfully used during the operation without abnormal bleeding,guide plate fracture,nerve fracture and other conditions.Compared with the preoperative simulation,the postoperative distance between the corresponding points of the left guide plate fixation point,the right guide plate fixation point,the left mental nodule point,the right mental nodule point and the mental preoperative simulation point was 0.23mm,0.28mm,0.56mm,0.73mm and 0.91mm,respectively.At the set reference point,the postoperative actual and preoperative simulation errors were less than 1mm.Conclusion(1)The 3d CT model reconstructed by digital technique and the appropriate 3d CT measurement indexes can effectively reflect various mental deformities.It can be used not only for the aesthetic study of chin,but also for the digital accurate diagnosis of mental deformity,as well as for the preoperative and postoperative comparative study,which is worthy of clinical promotion.(2)Classification based on the spatial location and morphological abnormalities of the chin can intuitively reflect the aesthetic defects of the chin,which has reference value for the diagnosis and treatment of plastic surgery.In addition,the causes of different classification deformities may be different,which deserves further study.(3)The mental osteotomy surgical program based on digital design and manufacturing technology has the advantages of accurate diagnosis,visual selection of preoperative design,simple,efficient and accurate intraoperative operation.Computer-aided design and 3D printing of mental osteotomy guide plate and positioning guide plate can well translate preoperative design into actual surgery.It can guide young doctors to master surgical skills as soon as possible and improve surgical accuracy.At the same time for the future operation navigation technology and robot surgery experience,the future has a broad prospect.