中文摘要：

目的探讨不同大小交互偶联的机械力作用兔前颌缝和颧颌缝改建的组织形态学变化。方法 2.5月龄体重2.0-2.5kg雄性日本大白兔,通过在双侧前颌缝近远中两侧的上颌骨与前颌骨中分别植入微种植钉,镍钛拉簧双侧对称性即刻加载不同力值（50、100、150、200、250、300g/侧）7d,使左右的前颌缝受到来自拉簧的压缩应力;相对处于上颌骨远中的颧颌缝受到牵张应力,来观察在这种交互偶联力作用下,兔前颌缝和颧颌缝改建的形态学和组织学改变。结果实验期间,随着力值增加实验兔覆盖减小,覆改变不显著。苏木精-伊红染色组织学观察可见,各实验小组从50g/侧到250g/侧,随着力值增加前颌缝和颧颌缝分别发生破骨和成骨的改建,改建基本都处于生理范围,到250g/侧时两条骨缝的改建最活跃。当加力为300g/侧时,骨缝结构基本消失,该力值已超出兔骨缝改建所能承受的生理范围。结论在生理范围内,不同机械力值作用兔骨缝引起的骨改建,在250g/侧时处于最活跃状态。

英文摘要：

Objective To examine the histomorphological changes during the remodeling of premaxillary suture and zygomaticomaxillary suture of rabbits by using different mechanical forces. Methods Micro-implants were placed in premaxillary and maxillary suture, respectively,as the anchorage in the male Japanese rabbits at the age of 2.5 month with the weight from 2.0 to 2.5 kg. Mechanical force was produced by nickel titanium spring between these anchorages on both sides immediately. Different forces（50,100,150,200,250,300 g/side） were exerted directly on the premaxillary suture for 7 days, which also caused a tensile force to zygomaticomaxillary suture at the same time. The overbite and overjet of the incisors of rabbits were measured. Histomorphological changes were observed by hematoxylin-eosin（HE）staining. Results The overjet was decreased significantly under different forces and the overbite had no significant changes at 7 days. HE staining showed that bone resorption and formation occurred to some extent in premaxillary suture and zygomaticomaxillary suture when the force was between 50 g/side to 250 g/side. Remodeling of sutures happened most obviously in 250 g/side group. In 300 g/side group, the normal construction of sutures disappeared, suggesting that 300 g/side was beyond the physiological ranges of the remodeling of suture in rabbits. Conclusion Physiological remodeling of sutures was most active when 250 g/side force was exerted on sutures.