Abstract
Ultrasonic dental scaler is an instrument to remove dental calculi using ultrasonic vibration of a transducer. The conventional transducer has a hose to provide water to scaling point. The hose causes attenuation of the ultrasonic vibration. This paper describes a new transducer design to avoid the attenuation. Design decision by comparison of two types of transducer designs is reported. Additionally, the ultrasonic transducer is used in resonance condition. The resonance frequency, however, is shifted according to value of input voltage to the transducer and condition of contact with tooth or gum. This paper presents a resonance frequency tracing system to solve the frequency shift. Step responses are specified as evaluation of the system. Application of the system to diagnosis is also discussed. Experiments on measurement of object properties are reported. The results indicate possibility that dental health can be investigated by observing the frequency shift during the scaler operation.
