Ultrasonic dental scalers

How it works
The piezo in the ultrasonic dental scalers operates as a transducer by rapidly changing size when excited by an electrical signal. The scaler vibrates against the tooth, creating sound waves that break apart the hard calculus on the tooth structure. Water also flows out of the scaler and combined with the vibration, this produces millions of tiny air bubbles that collapse with enormous energy resulting the cell walls of bacteria in the plaque to break up.

Piezo scalers usually operate in the low ultrasonic range, typically 24-36 kHz, with peak powers reaching up to 25 W. The tool can be adapted to several tasks from cleaning to extraction, simply by changing the tip and power level.

Which piezo elements can be used for ultrasonic dental scalers? 
Such ultrasonic transducers are usually constructed with piezo monolayer of a ring shape, which are bolted to a coupling horn that provides an amplification of the movement. Hard-doped materials such as NCE80 are preferred in order to deliver the high power without excessive heat generation. The ring components can be replaced by multilayer piezos, which will allow a drastic reduction of the operating voltage keeping the same performance and as such reduce the electrical safety requirement when operating in the human body.