基于纳米压痕技术的人龈上结石弹性模量及硬度的测量

Study on Elastic Modulus and Hardness of Supra-Gingival Dental Calculus by Nanoindentation

目的测量人龈上结石的弹性模量及硬度,为牙科治疗机器人力反馈装置的研发提供依据。方法采用5例成人牙周炎患者龈上结石为样本,对牙结石样本进行镶样,抛磨处理,制备成尺寸为4mm×10mm×10mm的试件,利用纳米压痕技术对样本的弹性模量及硬度进行测量。结果制备10个牙结石样本,共获取100条压痕曲线,其中可用曲线95条(删除无法拟合的曲线及错误曲线),牙结石弹性模量的变化范围为7. 27～53. 60GPa,平均值为25. 22GPa;硬度的变化范围为0. 11～2. 25GPa,平均值为0. 67GPa。结论龈上结石弹性模量及硬度值并非一确定值,具有离散性。

Objective To measure elastic modulus and hardness of supra-gingival dental calculus and to provide basis for force feedback system of dental robotics. Methods Ten specimen of supra-gingival dental calculus were obtained from 5 patients with periodontal disease. The cross-section view, 4mm×10mm×10mm in size was prepared in an epoxy mount and polished. Nanoindentation method was used to survey elastic modulus and hardness of supra-gingival calculus. Results Among the 10 specimens, a total of 100 indentation curves were harvested and 95 can be calculated （excluding error and unable fitted curves）.The elastic modulus is ranging from 7.27GPa to 53.60GPa with the average of 25.22GPa;the hardness s is ranging from 0.11GPa to 2.25GPa and the average is 0.67GPa. Conclusion Using a nano -indentor to measure elastic modulus and hardness of supra-gingival calculus is practicable.