Excuse me, what is the specific usage of Mo Yan's tooth beauty instrument? Is it useful?

The use of Mo Yan's tooth beauty instrument is divided into three steps: 1, and the gel is evenly applied to the teeth; 2. Connect the dental instrument to the mobile phone OTG, press the dental instrument switch and put it in your mouth to bite; 3. After the instrument is automatically turned off, you can brush your teeth with the matching toothpaste and rinse the tooth beauty instrument with clear water. It is very convenient to use. After a course of treatment, the contrast color card is 7 degrees white.