颌间Ⅲ类矫形力对青春期恒河猴颞下颌关节改建作用的影像学研究

目的　评价颌间Ⅲ类矫形力对颞下颌关节的作用及影响。方法　选用青春生长发育期雌性恒河猴6 只,分为3月、6月实验组和对照组。实验组戴用Ⅲ类双阻板磁力矫治器,对照组不戴。实验前后拍摄X线头颅侧位片和CT断层扫描片,采用计算机头影测量系统进行X线测量分析;电子游标卡尺、图像分析系统对颞下颌关节间隙进行测量并行统计学处理。结果　①头影测量表明,与对照组相比,实验组位发生改变,上颌骨呈生长加快趋势,下颌骨呈生长减慢趋势,下颌骨长度未见变短。②CT片测量表明,实验组与对照组相比关节后间隙减小,前间隙增大,差异有统计学意义(P<0·01);但两实验组间差异无统计学意义。结论　在颌间Ⅲ类矫形力作用下,实验组位发生改变,上颌生长加快下颌生长减慢;颞下颌关节间隙发生改变,关节前间隙增大,后间隙减小。

The Effect of Class Ⅲ Intermaxillary Functional Orthopedic Force on the Remodeling of Pubescent Rhesus Monkeys'' Temporomandibular Joint:An Radiographic Study

OBJECTIVE: To study the effect of Class III intermaxillary functional orthopedic force on the remodeling of pubescent Rhesus monkeys' TMJ for different lengths of time. METHODS: Six pubescent Rhesus monkeys were divided into test group and control group. Monkeys in the test group wore TMAIII while the control group did not. Cephalometric technology and CT scanning were employed in this study. RESULTS: 1. Compared with the control groups, the cephalometric results showed that the relationship of the occlusion changed in the test groups. The growth of the maxilla was promoted and the development of the mandible was inhibited, but the mandibular length was not decreased. 2. Compared with the control groups, CT scanning results showed that the posterior space of TMJ in the test group narrowed and the anterior space widened. There was a statistical difference between the test group and the control group(P < 0.01), but no difference within the test group. CONCLUSION: Under Class III Orthopedic therapy, the occlusion relation was changed. The growth of maxilla was promoted and the development of mandible was inhibited. The posterior space of TMJ narrowed and the anterior space widened in test group.