What is the principle of electric toothbrush cleaning teeth? What are the advantages over brushing your teeth manually? 2021-01-07
If it is more domestic "sonic electric toothbrush". Simply put, it is to simulate the principle of hand brushing, up and down repeatedly brush, but the speed is very fast, dozens of times the speed of the hand. Things to note about the use of the sonic electric toothbrush include: the method of brus
