人颞下颌关节盘不同矢状层面前后向拉伸力学特性的比较研究

The comparing study on the stretching characteristics of human temporomandibular disc at different sagittal sections

目的:探讨人颞下颌关节盘内、中、外不同部位拉伸力学特性的差异。材料和方法:Instron1122型拉伸实验机,自制夹头;人颞下颌关节盘3个,取外、外中、内中、内四个部位分别作拉伸实验,两部摄象机不同方向同步拍摄拉伸过程,计算机图象分析、计算各部弹性模量(E)和宽度泊松比(μ宽度)及厚度泊松比(μ厚度)。结果:关节盘的E为1.45±0.46兆帕～ 2.69±1.87兆帕,其中关节盘内中份者较小(1.45±0.46兆帕);μ宽度为0.31±0.13～0.44±0.04,μ厚度为0.18±0.0～ 40.44±0.05,关节盘内侧份和内中份的μ厚度均较小。结论:关节盘内、外侧份拉伸力学特性有明显差异,可能与其相应的功能需要有关。

Objective: To investigate whether there exist the difference of the stretching characteristics of the human TMJdisc among the different sagittal sections. Materials and Methods: Three discs of temporomandibular joint from humancorpse were tested on Instron tensile testing machine type 1122,with special designed clap. The test pieces were 0.5mmwidth, separately taken by a special knife from each quarter of lateral, lateral-middle, medial-middle and medial of the discin sagittal direction. Two video-cassette recorders were applied in directions perpendicular to each other for track-recordof the whole stretch process. Image data was then captured with the computer-aided processing system. Stretching Young'sModulous and Poisson's Ratio was calculated. Results: It showed that the values of the Stretching Young's Modulous werefrom 1.45±0.46 to 2.69±1.87 Mpa, the medial-middle took the smallest of 1.45±0.46. The Width Poisson's Ratiowere 0.31±0.13 to 0.44±0.04 and the Thick Poisson's Ratio were 0.18±0.04 to 0.44±0.05, with the smallestThick Poisson's Ratio at the medial and medial-middle parts. Conclusions: There is a significant difference for the StretchingYoung's Modulous and Poisson's Ratio among the different saggittal sections of the human temporomandibular joint disc.It is believed that the characteristics being in need of their relative functions.