Periodontitis and gingivitis are the two most common diseases of the periodontium. These two diseases are both related and distinct. Generally speaking gingivitis is the early stage of periodontitis, which routinely appears first, and gingivitis gradually develops and once attachment loss is formed, periodontitis is formed. On the other hand, once gingivitis is detected, treated and handled in a timely manner, its adverse effects are reversible. However, once periodontitis begins, its symptoms are irreversible. The typical symptoms of gingivitis are swelling and redness of the gums as well as bleeding, which is often manifested as bleeding under irritation, but gingivitis can usually return to normal gum shape after a period of treatment and does not leave significant after-effects. Once periodontitis has developed, it means that there is recession of the gums, resorption of the alveolar bone, and eventually the possibility of loosening and loss of teeth. The treatment for periodontitis is usually controlled so that it does not progress further, but it is difficult to get the periodontium to grow new gums again.