Ultrasonic scalers are effective tools in removing built-up plaque. Yet the formation of tiny bubbles around the heads of these devices is key to the cleaning process, reports the University of Birmingham in the United Kingdom. In fact, its researchers believe their findings could improve ultrasonic scaler performance.
“Removing dental plaque and calculus—that is the buildup of what we know as tartar or hard plaque—is a big part of maintaining oral health and a regular occurrence in dental checkups,” said Dr. Damien Walmsley of the university’s school of dentistry. “These findings will help us to understand how to make the tools as effective as possible.”
The study examined an A-dec Satelec ultrasonic scaler operating at 29 kHz with 3 different shaped tips at medium and high operating power using high-speed imaging at 15,000, 90,000, and 250,000 frames per second. Tip displacement was recorded using scanning laser vibrometry.
The high-speed cameras captured the bubble formation, or cavitation, of water around each scaler’s head. The cavitation occurred at the free end of the tip and then increased with power. The area and width of the cavitation cloud varied between tips of different shapes.
“Other studies we have done, using electron microscopy, have shown that removal of plaque biofilm is increased when cavitation is increased,” said PhD student Nina Vyas, lead author of the study. “We can therefore say that altering the shape and power of these commonly used tools makes them more effective and, hopefully, pain-free.”
The study, “High Speed Imaging of Cavitation around Dental Ultrasonic Scaler Tips,” was published by PLOS ONE.