Gingivitis is a mild inflammation of the gum. In this drawing, it is represented on the right part of the gum, the red part, which characterizes the inflammation with swelling of the gum. It is associated here with a plaque of tartar on the periphery of the lower part of the dental crown and the upper part of the collar. Gingivitis can quickly spread to the underlying tissues and turn into periodontitis which is not the case in this drawing.