叩齿紧咬运动中松动牙动态力变化特点的研究

目的:研究紧咬、叩齿运动中松动牙牙合力的动态变化特征。方法:选择19例单侧下颌第一磨牙松动的患者,用PVDF动态牙合力仪测量健侧和患侧下颌第一磨牙节律性叩齿和紧咬运动中牙合力动态变化曲线,分析最大牙合力峰值和到达峰值的时间,对两侧的测量结果进行分析。结果:叩齿运动中健侧下颌第一磨牙牙合力峰值平均为25kg,到达峰值的时间为108ms;患侧的分别为21kg和126ms;紧咬运动中健侧下颌第一磨牙牙合力峰值平均为27kg,到达峰值的时间为768ms;患侧的分别为23kg和1023ms;经配对t检验,健侧与患侧的峰值及到达峰值的时间差异均有显著性。结论:牙齿松动导致咀嚼功能降低,牙合力值和牙合力上升的速度均降低。

The dynamic characters of bite force changing in tapping and opening- closing movement of loosen teeth

Objective: To determine the dynamic characters of bite force changing in rhythmic tapping and opening-closing with maximal force in loosen teeth. Methods: 19 patients with only one loosen first lower molar were selected. A PVDF piezoelectrical transducer-based instrument for dynamic bite force was used for dynamic bite force recording. The peak value and the time needed of the loosen teeth and the healthy teeth on the other sides were analysed. Results: The mean peak value of bite force of healthy first lower molars during rhythmic tapping movements were 25 kg, to which 108 ms needed, as to the loosen teeth, the values were 21 kg and 126 ms; in the movements of opening-closing with maximal force of healthy teeth, the peak values were 27 kg and 768 ms needed, as to the loosen teeth, the values were 23 kg and 1023 ms. There were significant difference between the healthy and loosen teeth, both the force and the time. Conclusion: Tooth loosen would lead to poor function, both the bite force and the speed of the bite force increasing declined.