单侧部分后牙锁者的咀嚼运动轨迹研究

Astudy of the effect of posterior teeth with reverse cross-bite on chewing mov ement

目的 :探讨单侧部分后牙锁牙合对咀嚼运动轨迹的影响。方法 :16名单侧部分后牙锁牙合者 ,12名正常牙合对照 ,K6 Ⅰ型下颌运动轨迹描记仪 ,测试分别以左、右侧重复咀嚼 5次口香糖时的运动轨迹和速度。结果 :①对照组冠状面咀嚼运动呈规则的环形 ,锁牙合组多为垂直出入形 ( 5 9.3 8% )或咀嚼侧出入型 (同出同入型 ,2 1.88% )咀嚼环 ;②锁牙合组咀嚼时向后运动的幅度、咬合引导轨迹与水平面的夹角、随意咀嚼终点平均速度 ,明显大于对照组。结论 :单侧部分后牙锁牙合 。

Objective:To investigate the effect of partial p osterior teeth with reverse cross-bite at one side of mandible on the chewing m ovement. Methods: 16 university students with partial posterior teeth reverse cross-bite and 12 with normal occlusion were included, 5 cycles o f gum chewing movement with left and right side separately were recorded with K6 -Ⅰmandibular kinesiograph (MKG) for the trace and velocity. Results: ①The chewing movement recorded in frontal plane was with a typical cycl e in controls while that in reverse cross-bite individuals was vertically in an d/or out type (59.38%), as well as in and out in same direction type (21.88%). ②Chewing movement in reverse cross-bite patients was in posterior direction, together with a larger angle of closing trace to horizontal plane and higher che wing terminal velocity. Conclusion: Partial posterior teeth with reverse cross-bite at one side have significant effect on both direction and v elocity of chewing movement.