A recently introduced feature in an air-driven handpiece combines some of the benefits of traditional air-driven and electric handpieces into one instrument. Two new technologies incorporated into this dental handpiece are speed sensing intelligence (SSI) and superior turbine suspension (STS). These features allow this handpiece to deliver the benefits of constant torque at high speeds when performing various dental procedures, specifically cutting enamel and dentin and removing or sectioning through different types of restorative materials, including metal and zirconium.

According to the manufacturer, some of the benefits of these technologies in an air-driven handpiece are: automatic optimization of power, that is, constant speed under load to avoid stalling; delivery of smooth, constant power and control for maximum cutting efficiency and faster removal of material; speed adjustment of the bur when it is not under load to minimize wear on the bearings; and allowing the handpiece to operate at 330,000 RPM under load without bur chatter or deflection.

Because an air-driven handpiece with automatic torque control can literally “sense” the degree of “resistance” when cutting through various materials, constant speed and torque are delivered to the cutting instrument, making it unique among traditional high-speed air-driven dental handpieces. In the author’s experience, when cutting through enamel, the hardest substance in the body, this type of device gives the operator a fast, efficient cut that leaves the preparation margins ultra smooth. Cutting depth cuts for minimal-preparation veneers entirely in enamel can be performed with precision.

As the rotary instrument engages the softer dentin in a preparation, the handpiece “senses” it and reduces the workload on the handpiece while maintaining constant torque. Cutting through restorative materials, from metal amalgam to zirconium substructures, puts a high degree of strain on the turbines of traditional air-driven handpieces and wear on their turbines. Having the ability to automatically adjust speed and torque based on the resistance of the substrate improves efficiency, with less wear and tear on the handpiece itself.

Control during tooth preparation and automatic adjustments in torque to cut enamel and dentin with equal amount of ease and efficiency is, of course, greatly beneficial. However, in a clinical world where dentistry is moving away from metal-based restorative materials towards high-strength porcelain and zirconia restorations, clinicians will need a handpiece that can efficiently remove these materials when they need replacement. Many traditional high-speed handpieces will be strained beyond their limits performing these procedures on a daily basis, which will lead to costly repairs and early replacement.