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

研究了一种小而轻的触觉传感器。经过几次修改，一个更小更轻的传感器被成功地开发出来。它已被应用于人类软组织，以定量和无创的方式评估刚度。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。传感器的尖端是一个直径0.5毫米，长35毫米的半球。用触觉传感器和显微硬度测试分别测定了健全牙本质、人工牙釉质病变、健全牙本质和龋齿牙本质的硬度。触觉传感器能够定量检测30 ~ 70 g载荷下人工牙釉质病变的硬度差异。触觉传感器测得的硬度与显微硬度试验测得的硬度呈正相关。触觉传感器能够确定牙齿硬组织的所有硬度水平。另一方面，触觉传感器测得的橡胶压痕材料硬度与橡胶硬度测试结果无相关性。

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.