下颌运动轨迹描记仪在不同型人群中的应用

Application of mandibular kinesiography in dental occlusion

背景:错畸形者牙列牙弓的不协调直接影响着下颌运动的发挥,甚至会造成颞下颌关节的超负荷,最终发生病变。目的:测量各类型人群的下颌运动特点。方法:(1)选取符合实验标准的自愿者33人,平均年龄21.71岁,男性1人,女性32人。分为4组,正常对照组10人,安氏Ⅰ类错组10人,安氏Ⅱ类错组8人,安氏Ⅲ类错组5人;(2)用描记仪测量各组下颌各运动的轨迹,以及下颌姿势位到牙尖交错位的运动轨迹;(3)用SPSS17.0软件进行统计学分析,得出各组人群下颌运动轨迹特点和差异。结果与结论:(1)开闭口、左侧、右侧、前伸运动时,安氏Ⅱ类错畸形组人群右下颌第1磨牙运动轨迹的最大距离与其他3组比较,差异有显著性意义(P<0.05);(2)做快速开闭口运动时,正常对照组下颌中切牙切点运动的垂直距离与安氏Ⅰ类错畸形组、安氏Ⅲ类错畸形组比较差异有显著性意义(<0.05);正常对照组最大距离与安氏Ⅰ类错畸形组比较差异有显著性意义(P<0.05);安氏Ⅱ类错畸形组右下颌第1磨牙运动的垂直距离与其余3组比较差异有显著性意义(P<0.05);正常对照组最快开口速度与安氏Ⅱ类错畸形组、安氏Ⅲ类错畸形组比较差异有显著性意义(P<0.05);(3)各组人群息止间隙不存在显著性差异。结果提示,不同型人群下颌中切牙运动轨迹、下颌第1磨牙运动轨迹和运动速度不同,因而推断错畸形可以影响下颌运动的方向、范围和速度。

BACKGROUND：Maxil ofacial malformation limits the function of the mandible, produces the overload of the temporalmandibular joint leading to oral diseases. OBJECTIVE：To measure the characteristics of mandibular movement in populations with various types of dental occlusion. METHODS：Thirty-three volunteers （1 male and 32 females, mean age 21.71 years） meeting the inclusion criteria were enrol ed from Dalian Medical University, China and divided into four groups：normal control （n=10）, Angle’s class I, II, III malocclusion （n=10, 8, 5）. The protrusion, lateral, opening motion trace of mandibular central incisor and the right mandibular first molar, and the trace from mandibular postural position to intercuspal position were measured using the mandibular kinesiograph. The features of different occlusal patterns were analyzed using SPSS 17.0 software. RESULTS AND CONCLUSION：In the trace of protrusion, lateral, opening and closing motion, there were significant differences in the trace of the right mandibular first molar’s Max.Slant between Angle’s class II malocclusion group and the other three groups （P〈0.05）. In the trace of open wide and close fast, there were significant differences in the trace of mandibular central incisor in vertical distances between normal control group and Angle’s class I, III malocclusion groups （P〈0.05）;there were significant differences in the trace of mandibular central incisor in Max.Slant between normal control group and Angle’s class I malocclusion group （P〈0.05）;there were significant differences in the trace of the right mandibular first molar in vertical distances between Angle’s class II malocclusion group and the other three groups （P〈0.05）;there were significant differences in the trace of the right mandibular first molar in Max.Opening velocity between normal control group and Angle’s class II, III malocclusion groups （P〈0.05）. There were no significant differences in free space between the four groups （P〉0.05）. These results indicate that there are differences in the trace of mandibular central incisor and the trace of the right mandibular first molar in range and speed between different occlusal patterns. We can draw a conclusion that malocclusion has effects on the direction, range and speed of mandibular movement.