测试人牙周膜粘弹性力学特性的纳米压痕实验条件研究

Study on the experimental conditions of nano-indentation test for investigating the viscoelastic properties of human periodontal ligament

目的研究通过纳米压痕实验测试人牙周膜粘弹性性能的实验条件。方法预备人牙周膜样本,在保湿环境下使用平头压头对人牙周膜分别进行基于纳米压痕的蠕变实验和约化弹性模量测试。根据控制变量法设置实验方案,测试不同实验条件对实验结果的影响。结果得到最佳实验参数范围:基于纳米压痕的蠕变实验的加载率为0.3~0.5 mN/s;基于纳米压痕的约化弹性模量测试的保载时间为25 s和峰值载荷为2~3 mN。并得到了人牙周膜的纳米压痕蠕变曲线和0.012~6.840 MPa的约化弹性模量范围。结论验证了人牙周膜具有粘弹性性质,并提出了适用于人牙周膜纳米压痕实验的条件。

Objective To design experimental conditions via nano-indentation test,in order to investigate the viscoelastic properties of the human periodontal ligament(PDL).Methods After preparation of human PDL samples,the nano-indentation creep test and conventional reduced elastic modulus test were carried out by a flat punch in a moistful environment.The experimental scheme was set up according to the control variable method,and the influences of different experimental conditions on the experimental outcomes were analyzed.Results The optimum parameters were obtained as follows:the nano-indentation creep test demanded the loading rate as 0.3~0.5 mN/s;the holding time of 25 s and peak load of 2~3 mN were suitable for the conventional nano-indentation test.The nano-indentation creep curve of human periodontal ligament and the reduced elastic modulus range of 0.012~6.840 MPa were obtained.Conclusion The viscoelastic properties of human periodontal ligament are verified.The experimental conditions that are applicable to nano-indentation test for human periodontal ligament are proposed.