Comparison of the virtual surgical planning position of maxilla and condyle with the postoperative real position in patients with mandibular protrusion
10.19723/j.issn.1671-167X.2024.01.012
- VernacularTitle:下颌前突畸形患者上颌骨及髁突虚拟位置与术后现实位置的比较
- Author:
Andong CAI
1
,
2
;
Xiaoxia WANG
;
Wenjuan ZHOU
;
Zhonghao LIU
Author Information
1. 北京大学口腔医学院·口腔医院口腔颌面外科,国家口腔医学中心,国家口腔疾病临床医学研究中心,口腔生物材料和数字诊疗装备国家工程研究中心,口腔数字医学北京市重点实验室,北京 100081
2. 滨州医学院口腔医学院,数字化口腔医学山东省高校特色实验室,山东烟台 264003
- Keywords:
Digital technology;
Orthognathic surgical procedures;
Angle class Ⅲ malocclusion
- From:
Journal of Peking University(Health Sciences)
2024;56(1):74-80
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To compare the difference between virtual surgical planning(VSP)position and postoperative real position of maxilla and condyle,and to explore the degree of intraoperative realization of VSP after orthognathic surgery.Methods:In this study,36 patients with mandibular protrusion de-formity from January 2022 to December 2022 were included.All the patients had been done bilateral sagittal split ramus osteotomy(SSRO)combined with Le Fort Ⅰ osteotomy under guidance of VSP.The VSP data(T0)and 1-week postoperative CT(T1)were collected,the 3D model of postoperative CT was established and segmented into upper and lower jaws in CCMF Plan software.At the same time,accor-ding to the morphology of palatal folds,the virtual design was registered with the postoperative model,and the unclear maxillary dentition in the postoperative model was replaced.Then the postoperative model was matched with VSP model by registration of upper skull anatomy that was not affected by the opera-tion.The three-dimensional reference plane and coordinate system were established.Selecting anatomical landmarks and their connections of condyle and maxilla for the measurement,we compared the coordinate changes of marker points in three directions,and the angle changes between the line connecting the marker points and the reference plane to analyze the positional deviation and the angle deviation of the postoperative condyle and maxilla compared to VSP.Results:The postoperative real position of the maxilla deviates from the VSP by nearly 1 mm in the horizontal and vertical directions,and the anteropos-terior deviation was about 1.5 mm.In addition,most patients had a certain degree of counterclockwise rotation of the maxilla after surgery.Most of the bilateral condyle moved forward,outward and downward(the average distance deviation was 0.15 mm,1.54 mm,2.19 mm,respectively),and rotated forward,outward and upward(the average degree deviation was 4.32°,1.02°,0.86°,respectively)compared with the VSP.Conclusion:VSP can be mostly achieved by assistance of 3D printed occlusal plates,but there are certain deviations in the postoperative real position of maxilla and condyle compared with VSP,which may be related to the rotation axis of the mandible in the VSP.It is necessary to use patient personalized condylar rotation axis for VSP,and apply condylar positioning device to further improve surgical accuracy.
