• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Microscale Material Properties of Bone and the Mineralized Tissues of the Intervertebral Disc-Vertebral Body Interface.
【24h】

Microscale Material Properties of Bone and the Mineralized Tissues of the Intervertebral Disc-Vertebral Body Interface.

机译：骨和椎间盘椎体界面矿化组织的骨微尺度材料特性。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The objective of this dissertation is to understand the influences of material structure on the properties, function and failure of biological connective tissues. Biological interfaces are becoming an increasingly studied system within mechanics and tissue engineering as a model for attaching dissimilar materials. The elastic modulus of bone (≈ 20 GPa) and cartilage (≈ 0.1-1 MPa) differ over orders of magnitude, which should intuitively create high stress concentrations and failure at the interface. Yet, these natural interface systems rarely fail in vivo, and the mechanism by which loads are transferred between tissues has not yet been established. Tissue quality is one major contributor to the mechanical behavior of bone and cartilage, and is defined by properties such as collagen orientation, mineral volume fraction, porosity and tissue geometry. These properties have yet to be established at the bone-cartilage interface in the spine, and the lack of quantitative data on material microstructure and behavior limits treatments and tissue engineering construct design.;In this dissertation, second harmonic generation imaging, quantitative backscattered scanning electron imaging and nanoindentation are combined to characterize micrometer scale tissue quality and modulus in both bone and calcified cartilage. These techniques are utilized to: 1) determine the hierarchical micrometer to millimeter scale properties of lamellar bone, 2) quantify changes throughout development and aging at the human intervertebral disc-vertebral body junction, and 3) explore compressive fractures at this interface. This work is the first to provide quantitative data on the mineral volume fraction, collagen orientation and modulus from the same, undecalcified sections of tissue to corroborate tissue structure and mineralization and describe quantitative parameters of the interface.;The principal findings from this work indicate that the underlying matrix, or collagen, organization in mineralized biological tissues and at the bone-cartilage interface plays an important mechanical role. Nanoindentation measurements in osteonal bone are affected by location within the lamellar structure, even though mineral volume fraction within a single osteon is relatively consistent compared to the differences observed between bone and calcified cartilage. While increasing mineral volume fraction contributes to increases in modulus in the calcified cartilage layer of the vertebral body-intervertebral disc interface, significant scatter remains. The collagenous matrix structure and type of collagen appear to have a significant influence on modulus as well. Collagen fibers of the disc mineralize adjacent to the bone of the vertebral body, and the persistence of this attachment zone from adolescence through senescence indicates that it likely serves a mechanical function. Fiber insertions into thick calcified cartilage regions likely create mechanically robust anchor points at the osteochondral interface.
机译：本文的目的是了解材料结构对生物结缔组织的性质，功能和破坏的影响。生物接口正成为机械学和组织工程学中越来越多研究的系统，作为附着异种材料的模型。骨骼的弹性模量（＆ap; 20 GPa）和软骨（＆ap; 0.1-1 MPa）在数量级上有所不同，这应该直观地在界面处产生高应力集中和破坏。然而，这些天然界面系统很少在体内失效，并且尚未建立在组织之间转移负荷的机制。组织质量是骨骼和软骨机械行为的主要贡献者，并且由诸如胶原蛋白取向，矿物质体积分数，孔隙率和组织几何形状之类的属性定义。这些特性尚未在脊柱的骨-软骨界面建立，并且缺乏有关材料微观结构和行为的定量数据限制了治疗方法和组织工程构造设计。本论文中，二次谐波成像，定量背散射扫描电子成像和纳米压痕相结合来表征骨和钙化软骨的微米级组织质量和模量。这些技术可用于：1）确定层状骨的微米级到毫米级等级特性，2）量化人类椎间盘-椎体交界处整个发育和衰老过程中的变化，以及3）在该界面处探查压缩性骨折。这项工作是首次提供来自相同的未脱钙组织切片的矿物质体积分数，胶原蛋白取向和模量的定量数据，以证实组织结构和矿化作用并描述界面的定量参数。;这项工作的主要发现表明：矿化的生物组织中以及骨-骨界面处的基础基质或胶原蛋白组织起着重要的机械作用。尽管与观察到的骨与钙化软骨之间的差异相比，单个骨内的矿物质体积分数相对一致，但骨层骨中的纳米压痕测量受层状结构位置的影响。尽管增加的矿物质体积分数有助于增加椎体-椎间盘界面钙化软骨层中的模量，但仍然存在明显的散射。胶原基质结构和胶原类型似乎也对模量有重要影响。椎间盘的胶原纤维在邻近椎体骨骼的位置矿化，并且该附着区从青春期到衰老的持久性表明它可能具有机械功能。纤维插入较厚的钙化软骨区域可能会在骨软骨界面处产生机械坚固的锚固点。

著录项

  • 作者

    Paietta, Rachel C.;

  • 作者单位

    University of Colorado at Boulder.;

  • 授予单位 University of Colorado at Boulder.;
  • 学科 Engineering Mechanical.;Engineering Materials Science.
  • 学位 Ph.D.
  • 年度 2013
  • 页码 149 p.
  • 总页数 149
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号