Gingivitis is caused by not cleaning the mouth promptly after eating, with the presence of irritating factors around the teeth causing repeated outbreaks. For example, bleeding during brushing or eating. This situation requires teeth cleaning, which includes ultrasonic scaling to remove dental calculus and other basic causative factors. Only by removing the irritating factors and treating the cause, applying medicine around the gums and improving the bleeding condition, can the symptoms of gingivitis improve. If oral hygiene is not maintained after removal, over time, dental calculus or dental plaque can reattach around the teeth, leading to a recurrence of gingivitis.