At this stage, the disease is confined only to the gums without affecting the underlying bone. If gingivitis is not treated in time, it will lead to detachment of the gums from the tooth, creating a space between the gums and the tooth known as a pocket, this is called periodontitis. And subsequently, teeth will start shaking, sensitivity with cold food is present. Some time pus discharge, foul smell and painful swelling are present. If not treated, the disease can progress to such an extent that the tooth will fall off.