Tartar is often referred to as calculus on the surface of the teeth. Tartar is hard tissue formed by the gradual mineralization of bacteria on the surface of the teeth. There are two ways to remove tartar: the first is to scrape the teeth with a hand instrument. The first is to scrape the teeth with a hand instrument. This method is mainly applicable to the teeth under the gums, which is also known as subgingival tartar. Subgingival tartar also requires attention when scraping, so that the root surface of the teeth after the root surface is flat, is not conducive to the formation of tartar. The second is the application of ultrasonic cleaning, mainly for tartar above the gums. This tartar is visible to the naked eye and can be removed by applying an ultrasonic scaler. After removing the tartar, the surface of the teeth needs to be polished. After polishing, the surface of the teeth becomes smooth, which is not conducive to the re-formation of tartar.