My dentist is looking at replacing our ultrasonic scaler. What are the most important considerations when making a choice?
Consider the type of ultrasonic technology desired: magnetostrictive or piezoelectric. Either technology can be learned with education, practice, and time. Both technologies combine frequency and power for energy in addition to water for various functions.
Frequency refers to the speed of movement of the tip. Most units are autotuned with a preset frequency that tunes the cycles per second to maximum efficiency for each ultrasonic insert/tip (UIT). Typically, devices house a 25 kilohertz (kHz) or 30 kHz frequency. Dual frequency 25 kHz and 30 kHz magnetostrictive units are offered. Manually tuned units are also available in which frequency can be adjusted for tuning and deposit removal.
Power is the amplitude of the vibration controlling the distance the tip travels in one vibration, referred to as “tip displacement.” Increasing power causes the tip to travel further in one vibration, improving efficiency.
Amplitude varies between UITs. Some have power boosts or sensors that automatically increase the power for tenacious deposits. A new option is preset power settings on the unit base, which include low power settings for plaque biofilm and higher power settings for tenacious calculus.
The water control adjusts the volume for correct cavitation and temperature. A piezoelectric unit does not need water to cool the handpiece transducer as a magnetostrictive unit does. Water for both technologies produces cavitation, flushes irritants, stems bleeding, cools the tip, and increases visibility.
The UIT application to the tooth is different between magneto and piezo. All sides of the magnetostrictive UIT are adaptable. Historically, only the two lateral sides of a piezoelectric tip were adapted because of the linear tip movement. It has been reported, however, that both inserts and tips move in an elliptical pattern.1,2 Even so, manufacturers of piezoelectric units generally recommend adapting the two lateral sides.
Consider if the controls on the base are easily reached, engaged, and user friendly. Newer units have digital touchscreen controls for purging water lines, rinsing the field without cavitation, power level adjustments, and foot pedal settings. Portability is a factor. If the unit is stationary, assess the space for use and storage. Some units can be built into the operatory’s dental equipment.
Handpiece comfort and size relate to proper activation that is important for treatment effectiveness. Also, some handpieces have autoclavable sheaths, can rotate within the clinician’s hands, and have LED or fiber-optic options. Foot pedals vary in size and cordless options. With contemporary units, clinicians can tap the foot pedal to change how the ultrasonic functions.
Another consideration is compatibility of UITs. Some manufacturers offer more selection than others. Extra features include an air polishing function, irrigation unit, and lighting options.
When choosing a manufacturer, consider the reputation, warranty, and repair options, as well as use, care, and maintenance instructions. Also, compare performance and safety data. Many manufacturers offer education on best practices via sales representatives, literature, and video instruction.
Borrow units from manufacturers to try prior to purchasing. Evaluate unit size, power, and handpiece design. Develop a checklist of key factors and assess each unit according to your checklist. Conducting an online search of products before consulting with manufacturer representatives will provide much needed information.
- Lea SC, Felver B, Landini G & Walmsley AD. Three dimensional ultrasonic scaler probe oscillationsJ J Clin Perio. 2009;36:44–50.
- Lea SC, Landini G. Reconstruction of dental ultrasonic scaler 3D vibration patterns from phase-related data. Med Eng Phys. 2010;32:673–677.