Diagnoses are associated with common findings which are used to prescribe appropriate treatment.
Alternate terms: Inflamed gums.
Gingivitis is a reversible inflammation of the gingiva (commonly called "gums"), with no breakdown of the attachment fibers connecting them to the teeth and underlying bone. Gingivitis is the earliest and simplest form of gum disease. It is characterized by red, puffy gums that bleed easily (Figure 1), but may or may not be sore. The disease is most often caused by bacterial plaque, and is generally reversible with removal of the plaque and excellent oral hygiene.

Figure 1: Gingivitis. A moderately severe case of gingivitis characterized by swollen gingiva ("gums"), red tissue margins, and bleeding on light stimulation. The condition is usually due to poor oral hygiene.
If ignored, the bacteria and inflammation causing gingivitis will destroy the periodontal attachment fibers between the gums and teeth, allowing bacteria to invade and destroy the underlying bone. When the attachment fibers have been lost, the patient is diagnosed with periodontal disease, or "periodontitis".
Other conditions which may cause the gums to bleed easily
Other conditions may cause the gums to bleed easily, and may aggravate bacterial gingivitis. Some of these conditions are medically serious, and should be investigated if the patient's gingivitis seems unresponsive to tooth cleaning and improved oral hygiene.