The so-called calculus is formed by the precipitation of minerals from saliva, food and gingival fluid and deposited on the surface of the teeth, and its nature is similar to the scale in a kettle. Since calculus is formed slowly over time, it is not easy for us to pay attention to it, and we even feel that it is integrated with our teeth, and often ignore its harmful effects. In fact, on the one hand, the long-term pressure of calculus on the gums will lead to redness, swelling, bleeding, shrinkage and gradual separation from the roots of the teeth, and on the other hand, calculus provides a good place for bacteria to adhere and gather, and the presence of bacteria further aggravates the inflammatory process in the area. Although there is no method to stop the formation of calculus, it is possible to remove the formed calculus regularly by mechanical means, which is commonly known as scaling or cleaning. This is also a common and basic method of treating or preventing bleeding gums. The basic principle of scaling is to remove the calculus deposited on the surface of the teeth by mechanical means, and there are two common methods, namely the manual instrument method and the ultrasonic vibration method. For example, the ultrasonic waves may irritate some people and produce a sensitive reaction. This is normal, but you should not be too afraid of scaling because of this. When sensitivity occurs, you can explain to the doctor, and generally reduce the intensity of ultrasound most people can still accept. In the case of the manual instrumentation method, a certain amount of pain will occur as the instruments touch the inflamed gums. In both methods, the gums will bleed, and the amount of bleeding is related to the degree of gum inflammation. Some people feel that the gap between their teeth has become larger after scaling. In fact, as mentioned above, this is because the sensory organs of the mouth have become accustomed to the abnormal form of calculus attached to the surface of the teeth and feel rusty to the normal form of the teeth. Other people feel that their teeth seem to be looser after a cleaning. This is also an illusion. In fact, there is no change in the looseness of teeth before and after scaling, but the excessive calculus before scaling affects our perception of the looseness of the affected teeth, in this case, the calculus as an irritant of heavy inflammation must be removed, and the problem of loose teeth can be solved or improved by different ways of fixing loose teeth. There is no loss of teeth by scaling as long as the regular operating procedures are followed. Since the formation of calculus cannot be stopped yet, scaling is one of the measures for oral health maintenance in addition to the treatment of gingivitis and periodontitis, and needs to be performed regularly, generally once a year for adults, but due to the large individual differences in the growth rate of calculus, it can be increased or decreased according to individual circumstances.