半侧颜面短小畸形患儿非病变侧下颌骨形态改变特点

目的通过几何形态学方法分析比较半侧颜面短小（HFM）畸形患儿下颌骨非病变侧与正常下颌骨的形态差异。 方法收集2015年1月1日至2021年12月31日广州市妇女儿童医疗中心收治的16例HFM畸形Ⅱb及Ⅲ型患儿（1岁以下）三维CT数据，以同时期同年龄段16例无颅颌面畸形的儿童下颌骨CT为对照。对CT数据进行抽提三维模型，绘制非病变侧下颌骨水平面及矢状面投影，对投影进行标点，转化为坐标数据导入MorphoJ进行典型变量分析。将非病变侧下颌骨三维模型同正常组下颌骨模型三维叠印，显示患者组非病变侧下颌骨三维形态特点。 结果患者组典型非病变侧典型下颌骨同正常组典型下颌骨三维叠印提示，患者组非病变侧髁突向内偏曲，升支后倾，体部略外展，颏部略向前突。典型变量分析结果显示，患者组与对照组在水平面投影（马氏距离=6.472 9，P<0.001；普氏距离=0.047 7，P=0.026 2）和矢状面投影（马氏距离=6.422 7，P<0.001；普氏距离=0.059 6，P=0.000 6）差异均存在统计学意义。水平面投影可见患者组非病变侧颏部向对侧偏斜，颏部与体部交界区弯曲度较大，髁突横轴相对于体部向外旋转；矢状面投影可见患者组非病变侧体部-升支弯曲度减小，髁突沿长轴方向缩短。 结论HFM畸形患儿非病变侧较正常组差异明显，表现为颏部延长、颏部与体部交界区水平弯曲度较大、体部-升支矢状弯曲度减小、髁突横轴相对于体部向外旋、髁突沿长轴方向缩短等变化。

The geometric morphometric analysis of the unaffected side of hemifacial microsomia patients′ mandibles

ObjectiveTo analyze and compare the morphological differences between the unaffected mandibles of the hemifacial microsomia (HFM) patients and the normal children′s mandibles with a geometric morphometric method. MethodsThe three-dimensional CT data of 16 HFM patients were collected. The patients were under one year old when admitted to Guangzhou Women and Children′s Medical Center from January 1, 2015 to December 31, 2021, and categorized as type Ⅱ b and type Ⅲ. Normal mandible data of children with the same age were used as the control. Three-dimensional superimposition of CT data was performed, and the unaffected mandible projections on the horizontal and sagittal planes were drawn for geometric morphometric analysis. ResultsThree-dimensional superimposition indicated that the condyles of the unaffected mandibles deviated inward, with inclined posteriorly ramus, slightly abducted body and slightly forward protruded chin. There were significant differences between the patients and the control group in both horizontal (Mahalanobis distance = 6.472 9, P<0.001, Procrustes distance = 0.047 7, P=0.026 2) and sagittal projections (Mahalanobis distance = 6.422 7, P<0.001, Procrustes distance = 0.059 6, P=0.000 6) . The horizontal projection showed that the chin of the patient group deviated to the opposite side, whereas the area between the chin and body was more curved, and the horizonal axis of the condyle rotated outward relative to the body. The sagittal projection showed that the body-ramus curvature of the patient group reduced, and the condyle shortened along the long axis. ConclusionsThe unaffected side of HFM patients′ mandible was statistically different from that of the normal children. Alterations in the mandibles included chin elongation, increased horizontal curvature of the area between the chin and body, decreased sagittal curvature of the body-ramus, rotation of the condylar transverse axis outwardly relative to the body, and shortened condyle along the long axis.