骨性安氏Ⅲ类患者双颌手术后软硬组织变化的相关性研究

目的用X线头颅侧位定位片,研究经上颌Le Fort Ⅰ型前移和下颌后退术后的骨性安氏Ⅲ类患者软硬组织在水平关系上的移动比例.方法对20例骨性安氏Ⅲ类患者应用手术前后X线头颅侧位定位片的相同测量点在水平轴上的差值,进行相关软硬组织比值计算和相关系数的统计学处理.结果所有下颌测量点的相关软硬组织都有相关关系,r＞0.8,P＜0.00l.下颌除颏前点移动比值低于1外,其余为11关系.上颌鼻下点与相应骨组织的相关关系较差,r＜0.5,P＞0.05,无统计学意义.结论上颌鼻下点与相关骨组织的相关关系较差,受诸多因素影响.下颌骨定点明确.研究骨性安氏Ⅲ类患者双颌手术后的软硬组织比值变化,可为准确预测术后面容改善提供参考.

The Ratio of Soft and Hard after Bimaxillary Operations in Patients with Skeletal Class Ⅲ Malformations

OBJECTIVE: To study the ratio between soft and hard tissue on the horizontal plane after the operations of maxillary Le Fort I advancement osteotomy and mandibular setback osteotomy in patient with skeletal class III malformations. It can help to predict precisely the post-operational profile. METHODS: 20 patients with skeletal class III malformation were taken cephalometric films pre-and post-operationally. The coordinate of landmarks were given from two films by computer analysis system. Different values in X axis were analysed statistically. RESULTS: All mandibular soft tissue landmarks were correlated with hard tissue landmarks (r<0.5, P>0.05). The ratios were 1:1 except the Pogonion(<1:1). Point of Sn was not correlated with the maxillary hard tissue significantly(r<0.5, P>0.05). CONCLUSION: The poor correlation between maxillary Sn and hard tissue was affected by many factors. It is easy to mark the mandible landmarks clearly. The ratio should help to predict the post-operation profile in patients with skeletal class III malformations.