Pini M, Wiskott H W A, Scherrer S S, Botsis J, Belser U C
Laboratory of Applied Mechanics and Reliability Analysis, Swiss Federal Polytechnical School (EPFL), Lausanne, Switzerland.
J Periodontal Res. 2002 Aug;37(4):237-44. doi: 10.1034/j.1600-0765.2002.00344.x.
This study is part of a research program that aims to develop a constitutive three-dimensional model of the periodontal ligament (PDL) through the identification of pertinent material parameters. As part of this program, bovine PDL was utilized to establish stress-strain responses under tensile and compressive loading conditions. Fresh bovine molars were secured, frozen and prepared to appropriate dimensional specifications. Bar-shaped specimens that comprised portions of dentine, PDL and bone were produced. Push-pull tests were conducted using a specifically constructed loading machine. Full range monotonic stress-strain diagrams were generated. The effect of a rate increase on cyclic S-E diagrams was also determined. The influence of specimen thickness was expressed in terms of modulus of elasticity, strength, uniaxial maximizer strain, and strain energy density. The overall load-response was heavily hysteretic in compression. On the tensile side, after a steep rise, the curve tended to flatten out asymptotically. Variations in rate that spanned four orders of magnitude had no effect on reciprocal load responses. The E-modulus was in the 4-8 MPa range, the strength of the PDL was 1-2 MPa, the maximizer strain was at 45-60% and the strain energy density ranged between 0.3 and 0.4 MPa.
本研究是一项研究计划的一部分，该计划旨在通过确定相关材料参数来建立牙周韧带（PDL）的三维本构模型。作为该计划的一部分，利用牛的牙周韧带建立拉伸和压缩载荷条件下的应力-应变响应。获取新鲜牛磨牙，冷冻并制备成合适的尺寸规格。制作包含牙本质、牙周韧带和骨部分的条形标本。使用专门构建的加载机进行推拉试验。生成全范围单调应力-应变图。还确定了加载速率增加对循环应力-应变图的影响。标本厚度的影响通过弹性模量、强度、单轴最大应变和应变能密度来表示。压缩时的整体载荷响应具有严重的滞后现象。在拉伸侧，经过急剧上升后，曲线趋于渐近平缓。跨越四个数量级的加载速率变化对往复载荷响应没有影响。弹性模量在4-8兆帕范围内，牙周韧带的强度为1-2兆帕，最大应变在45-60%，应变能密度在0.3至0.4兆帕之间。
