节点文献
颌面部撞击损伤生物力学及其损伤模型的研究
Study of Biomechanics and Injury Model of Maxillofacial Impact Trauma
【作者】 薄斌;
【导师】 周树夏;
【作者基本信息】 第四军医大学 , 口腔临床医学(口腔颌面外科学), 2001, 博士
【摘要】 一、人下颌骨在拉伸载荷下的生物力学性质 目的:探讨应变率和骨密度与下颌骨拉伸力学性能的关系,建立下颌骨在拉伸载荷下的本构方程。 方法:以5具新鲜男性青年尸体的下颌骨为材料,对每具标本进行骨密度测定,然后制成标准试件在INSTRON材料试验机上进行电子拉伸,应变率分别为0.0003、0.003、0.03、0.3s-1,获得不同载荷下相应的应力-应变曲线。利用模型Y=a p bεc,以极限强度、弹性模量以及破坏应变为因变量(Y),以应变率和骨密度为自变量(X)进行非线性回归分析,并建立与应变率和骨密度相关的下颌骨拉伸本构方程。 结果:极限强度、弹性模量以及破坏应变相对于应变率和骨密度的非线性方程分另为σu=126.36ρ1.880.044(P<0.01)、E=25170.97ρ0.44ε0.052(P<0.01)和εu=0.0088ρ1.89ε-0.028(P<0.01)。下颌骨在拉伸载荷下的本构方程为σ=6309.57ρ0.96ε0.056ε0.80(P<0.01)。 结论:应变率和骨密度是影响下颌骨拉伸生物力学性质的重要因素。在一定应变率下可用获取的本构方程模拟下颌骨材料的生物力学特性。根据本构关系可以计算下颌骨在一定拉伸载荷作用下的应力大小,为损伤评判提供参考依据。二、人下颌骨在压缩载荷下的生物力学性质 目的:研究下颌骨在不同压缩载荷下的生物力学性质,建立下颌骨在压缩载荷下的本构方程。 方法:以5具新鲜男性青年尸体的下颌骨为材料,对每具标本进行骨密度测定,然后制成标准试件在INSTRON材料试验机上进行电子压
【Abstract】 1. Biomechanical Characters of Human Mandible Under Tension Load Objective: To study the biomechanical properties of human mandible under Tension Load and deduce the constitutive equation. Methods: 100 specimens taken from five mandible of fresh human cadavers were examined on INSTRON by a group of tensile tests at different strain rates (0.0003 0.003.. 0.03 0.3s?. Bone mineral density of every individual mandible was measured. The effect of strain rate(~), bone mineral density (p) on Young扢odulus (E), strength (cr ~) and ultimate strain ( ~ ~) was studied and the constitutive equation was deduced using the following model: Y=a p ~ Results: (1)u ~=126.36 p ~ E 0.044 ( P<0 .01) (2)E=25170.97p0? ~0.052 (~<o.oi) (3) 6j0.0088p E -0.026 (P<o.oi) (4) o~ =6309.57 ~ 0.96 6 0.056 E 0.80 (~<o .01) Conclusion: Strain rate and bone mineral density are important factors for the biomechanical properties of human mandible under tension Load. The results above may characterize the constitutive relation within small strain rates. From the constitutive equation, we could estimate the stress level of the mandible and assess the possibility and degree of mandible injury.
【Key words】 Mandible; Biomechanics; Tension; Strain rate; Bone mineral density;