Abstract
There are various methods to generate nanobubbles, and in this study, we experimented using a nanobubble generator with a high-density of stainless steel mesh nozzle to deliver nanobubble water (normal water and two kinds of mouthwash) stream through a tooth tray to clean bacteria coated on the denture. It showed that with various combinations of motor speed settings and pore diameters, a clearing rate of 95% or more could be achieved, while in some combinations, a clearing rate of 100% was possible. This confirmed the plaque removing the function of the nanobubble water streams. The motor speed setting of the nanobubble generator directly influenced the flow velocity and nanobubble diameter of the water stream. However, the nanobubble dimensions were found to have a significant impact on plaque removal. The bubble diameters and plaque removal efficacy were as follows: the smaller the diameter, the slower the flow velocity and the better the plaque removal. The nanobubble formation of mouthwash was better on plaque removal, compared with the soaking method. From these results, we theorized that plaque removal is influenced by the dimension of nanobubbles; smaller bubble diameter led to improved plaque removal efficacy.