人颞下颌关节关节盘、软骨及下颌骨的纳米弹性性能

NANOELASTIC PROPERTIES OF THE DISC, ARTICULAR CARTILAGE AND MANDIBLE FROM HUMAN TEMPOROMANDIBULAR JOINT(TMJ)

为探讨人颞下颌关节 (TMJ)各结构及下颌骨骨组织在纳米量级的材料力学性能的分布特点 ,采用原子力显微镜及毫微压痕测量法 ,对 3位正常成年男性 6个TMJ的关节盘、髁突软骨、关节窝软骨和下颌骨皮质骨、松质骨不同部位的纳米弹性模量进行测量和分析。结果显示 :人TMJ内关节盘、髁突软骨和关节窝软骨的不同部位具有不同的弹性模量 ,而各结构的弹性模量以前、内侧较高 ,中、后部及外侧较小。下颌骨皮质骨的弹性模量是松质骨的 2倍多 ,而下颌骨颊侧骨组织的弹性模量则明显低于舌侧。提示在纳米范围测量 ,TMJ内各结构以及下颌骨骨组织为非均质性材料 ,其不同结构或同一结构不同区域在纳米量级所承受的局部力学载荷不同。

The aim of the study is to determine the characteristics of the material properties of various structures in the temporomandibular joint (TMJ) and the mandibular bone tissues in nanoscopic scale. Using the atomic force microcopy (AFM) with the nanoindentation method, the nanomechanical properties of 6 discs, condylar cartilages and fossate cartilages in the TMJ, and 6 cortical and cancellous bones in the mandible of 3 normal adult men, were measured and analyzed. Results showed that marked differences were found in elastic properties among the different regions of the disc, articular cartilage in the TMJ. In the distribution of elastic modulus in these various structures, the elastic modulus was higher in the anterior and medial regions and lower in the middle, posterior and lateral regions. Otherwise, elastic modulus of the cortical bone in the mandible was approximately 2 times more than the cancellous bone. Elastic modulus in the buccal bone tissues of the mandible was more distinctly below one of the lingual site. The results suggested that the disc, condylar cartilage and fossate cartilage in the TMJ and the cortical and cancellous bone in the mandible were inhomogeneous with the nanolevel measurement. Different structures or various regions in the same structure were loaded by different local mechanical forces in the nanoscale.