High sensitive stiffness sensor for ultrasonic dental tool

Piezoelectric ultrasonic dental tool is gradually popular; however it may injure the soft tissue in the invasive implant surgery. Therefore, capability to distinguish hard and soft materials is the value-added technique. To reach this aim, we adopted piezoelectric ceramic ring integrated into the transducer as a stiffness sensor. Upon contact with a test sample, stiffness of the sample is detected by analyzing the voltage of the sensor. Different locations and thicknesses of the sensor are designed and the effect of these factors is investigated in this study. Under a small contact of 1 N, the sensor is able to achieve high stiffness sensitivity up to 1.68 V-m/kN.