无牙颌患者与正常人颅颌结构头影测量的比较研究

目的　采用X线头影测量方法 ,研究无牙颌患者与正常牙合人间面部高度、下颌位置等有关测量数据的差异。方法　对无牙颌患者在H及H-2 位置时分别拍摄头颅定位侧位X线片 ,并将其颅面结构测量值均数分别与正常牙合人正中牙合位时颅面结构各测量参考标准值比较。结果　正常牙合人及无牙颌患者在不同垂直距离下 ,SNA及N ANS测量数值高度一致。无牙颌患者在H及H-2 位与正常牙合人正中牙合位颅面结构相关测量角度及线距间比较均无显著性差异 (P >0 .0 5 )。但代表下颌位置变化的值MP FH、SGn FH、GoGn SN、PP GoGn、ANB及NPg FH、SND、SNB ,无牙颌患者在H、H-2 位与正常牙合人比较 ,后者恰位于前两者之间。结论　上颌骨结构不随牙列缺损、牙列缺失及垂直距离的改变发生变化。无牙颌患者在H、H-2 位较正常牙合人在息止颌位、正中牙合位的垂直距离有减小的趋势

A comparative cephalometric study on the craniomaxillary structure between the patients with edentulous jaws and the people with normal jaws

Objective To study the variations of the measurement data of the facial height and mandibular position between the patients with edentulous jaws and the people with normal occlusion by means of cephalometric roentgenography. Methods With the lateral radiographs on H and H -2 positions of the patients with edentulous jaws, the measurement data of the craniomaxillary structure were given an average T test. Results ① The measurement data of SNA and N ANS among people with normal occlusion and the patients with edentulous jaws were of the same height in different vertical dimensions. ② There was no significant difference( P > 0.05 ) on the measurement angle and linear distance between H and H -2 positions of the patients with edentulous jaws and central occlusion position of the craniofacial structure of the normal people. By comparing the index representing the change of mandibular location of edentulous jaw H and H -2 positions with that of the normal occlusion, the index of the latter was just within those of the former ones. Conclusions ① The structure of the upper jaw does not change with the variations of dentition defect, dentition loss or vertical dimensions. ② The vertical dimensions of the central jaw on the H and H -2 positions of the rest positions of the patients with edentulous jaw tend to decrease compared with those of the normal people.