Validation of Hardness Measurement of Dental Hard and Soft Tissue for Dental Clinic Using a Tactile Sensor : In vitro and in vivo Study

研究了一种体积小、重量轻的触觉传感器。经过几次修改，一个更小，更轻的传感器被成功开发出来。它已应用于人体软组织，以定量和无创的方式评估硬度。我们报告了一种使用触觉传感器测量牙齿硬组织硬度的方法。传感器的尖端是直径为0.5 mm、长度为35 mm的半球。用触觉传感器和显微硬度计分别测量健康牙釉质、人工牙釉质缺损、健康牙本质和龋坏牙本质的硬度。触觉传感器能够以定量的方式检测在30 g至70 g的载荷范围内的人工釉质病变的硬度差异。用触觉传感器测量的硬度与通过显微硬度测试测量的硬度正相关。触觉传感器能够测定牙体硬组织的所有硬度水平，而触觉传感器测定的橡胶印模材料硬度与橡胶硬度测试之间没有相关性。

A small and a lightweight sensor of tactile sensation was investigated. After several revisions a smaller and lighter sensor was successfully developed. It has been applied to human soft tissue to evaluate stiffness in a quantitative and noninvasive manner.We report a method for measuring the hardness of dental hard tissue using a tactile sensor. The tip of the sensor was a hemisphere measuring 0.5 mm in diameter and 35 mm in length. The hardness of sound enamel, artificial enamel lesions, sound and carious dentin was measured with the tactile sensor and by microhardness test. The tactile sensor was able to detect differences in hardness of artificial enamel lesions with loads ranging from 30 g to 70 g in a quantitative manner. The hardness measured with the tactile sensor was positively associated with that measured by the microhardness test. The tactile sensor was able to determine all the levels of hardness of the dental hard tissue.On the other hand, no correlation between the hardness of rubber impression materials measured with the tactile sensor and rubber-hardness test was observed.