目的:调查混合牙列期身体重心动摇与咬合力之间的关系。方法56名处于Hellman咬合发育Ⅲ期A阶段的健康小学生纳入研究。通过检查咬合平衡中点与中线的距离( X)关系,X≤5 mm被划分为正中组,X〉5 mm被划分为偏移组。使用自动姿态分析系统测定了身体平衡相关开闭眼时的重心动摇距离、重心动摇面积。使用牙齿压力感应装置Dental Prescale测定了咬合接触面积、平均咬合力、最大咬合压力,咬合力和咬合平衡。结果咬合接触面积和咬合力的测试结果男女分别为18.1 mm2、712.2 N和14.1 mm2、541.8 N,差异均具有统计学意义(P〈0.05)。咬合平衡中点正中组与偏移组的咬合接触面积、咬合力之间差异具有统计学意义(P 〈0.05)。咬合平衡中点正中组开、闭眼时期的重心动摇距离、面积明显小于偏移组,咬合平衡与开、闭眼时期的重心动摇距离、面积有关且具有统计学意义(P〈0.05)。重心动摇稳定组的咬合接触面积大于动摇组,两者差异具有统计学意义(P〈0.05)。结论 Hellman咬合发育Ⅲ期A阶段儿童咬合平衡和人体重心动摇存在相关性,咬合接触面积与身体重心动摇相互影响。
Objective To investigate the relationship between gravity center movement and bite force during the mixed dentition period. Methods Fifty-six healthy children with Hellman's Dental AgeⅢ A were selected from an ele-mentary school. The body balance, distance and area of gravity center movement ( GCM) were measured with automatic posture analytical devices. Occlusal abilities were measured with pressure-sensitive sheets ( Dental Prescale ) , including occlusal contacts area, average occlusal pressure, maximum occlusal pressure, occlusal force and occlusal balance. Re-sults The occlusal contact area and bite force test results of male and female group were 18. 1 mm2 , 712. 2 N and 14. 1 mm2, 541. 8 N, The differences were statistically significant (P〈0. 05). The occlusal contact area and bite force in occlusal balance point in normal group and offset group had correlation and statistical significance (P〈0. 05). The distance and area of postural sway during open and closed eyes period of occlusal balance point in normal group was much less than occlusal balance point in offset group. Occlusal balance and distance and area of postural sway druing open and closed eyes period had correlation and statistically significance (P 〈0. 05). Occlusal contact areas of gravity center movement were significantly greater than those of offset group (P〈0. 05). Conclusion There are correlation between A stage of Hellman occlusal development of children's occlusal balance and gravity center movement. Occlusal contact area and gravity center movement interact with each other.