The dental high-speed air turbine handpiece operates by rotating the impeller inside the handpiece with compressed air.
However, even if the inflow of the powered compressed air is stopped, the impeller rotates due to inertial rotation and createsnegative pressure inside the handpiece (backflow suction, commonly known as suck-back). Organic matter and microorganismsin the patient’s oral cavity flow into not only the inside of the handpiece but also other parts connected to the handpiece,causing contamination.
In this study, the Zero Suck-back Control Box (ZSCB) device, which was developed to prevent the reverse suction ofthe handpiece, was applied to five different handpieces and tested. After driving the five different handpieces with or withoutZSCB in the air, the presence or absence of suck-back was observed when they were stopped. In addition, when the handpiecewas driven using the fluorescent solution to imitate the oral environment, the fluorescent solution flowing into the insidedue to the reverse suction phenomenon was observed. It was evident that operating different handpieces with the ZSCBis effective in preventing the inhalation of external contaminants. In two different experiments conducted in this study, theuse of ZSCB was shown to be effective in preventing regurgitation in both atmospheric and immersion conditions.