Wu Bin, Wu Yang, Liu Mao, Liu Jingjing, Jiang Di, Ma Songyun, Yan Bin, Lu Yi
College of Mechanical and Electronic Engineering, Nanjing Forestry University, Nanjing 210037, China.
Department of Orthodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Nanjing 210029, China.
Materials (Basel). 2022 Aug 26;15(17):5912. doi: 10.3390/ma15175912.
In the process of orthodontic treatment, the remodeling of cancellous bone in alveolar bone (in this paper, cancellous bone in alveolar bone is abbreviated as CBAB) is key to promoting tooth movement. Studying the mechanical behavior of CBAB is helpful to predict the displacement of teeth and achieve the best effect of orthodontic treatment. Three CBAB samples were cut from alveolar bone around the root apex of human teeth. A uniaxial compression test was used to study the transient elastic properties of CBAB. A creep test was used to study the time-dependent viscoelastic properties of CBAB. Both tests were carried out at the loading rates of 0.02 mm/min, 0.1 mm/min and 0.5 mm/min. The results revealed that CBAB is a nonlinear viscoelastic and hyperelastic material. The stress−strain curve obtained from the uniaxial compression test could be divided into three stages: the collapse stage of the front section, the exponential stage of the middle section and the almost linear stage of the rear end. According to the strain−time curve obtained from the compression creep test, a trend of increasing strain over time was relatively obvious within the first 30 s. After 200 s, the curve gradually tended to plateau. Four hyperelastic models and three viscoelastic models were used to fit the test data. Finally, the fifth-order polynomial hyperelastic model (coefficient of determination “R2 > 0.999”) was used to describe the hyperelastic properties of CBAB, and the seven-parameter model of the generalized Kelvin modified model (“R2 > 0.98”) was used to describe the viscoelastic properties of CBAB.
在正畸治疗过程中，牙槽骨松质骨的重塑（本文中，牙槽骨松质骨简称为CBAB）是促进牙齿移动的关键。研究CBAB的力学行为有助于预测牙齿的位移并实现正畸治疗的最佳效果。从人类牙齿根尖周围的牙槽骨中切取了三个CBAB样本。采用单轴压缩试验研究CBAB的瞬态弹性特性。采用蠕变试验研究CBAB的时间依赖性粘弹性特性。两种试验均在0.02 mm/min、0.1 mm/min和0.5 mm/min的加载速率下进行。结果表明，CBAB是一种非线性粘弹性和超弹性材料。单轴压缩试验得到的应力-应变曲线可分为三个阶段：前段的塌陷阶段、中段的指数阶段和后端的近似线性阶段。根据压缩蠕变试验得到的应变-时间曲线，在前30 s内应变随时间增加的趋势较为明显。200 s后，曲线逐渐趋于平稳。使用四个超弹性模型和三个粘弹性模型对试验数据进行拟合。最后，采用五阶多项式超弹性模型（决定系数“R2>0.999”）描述CBAB的超弹性特性，采用广义开尔文修正模型的七参数模型（“R2>0.98”）描述CBAB的粘弹性特性。
