This fact sheet is designed to help you understand the two most common forms of gum disease: gingivitis and periodontitis. Gingivitis is a reversible disease of the gums. When plaque, caused by bacteria, is left on the teeth near the gums, your body responds in an adverse manner, resulting in an inflammatory response. Your gums may appear red, swollen and tender. With proper care and oral hygiene, gingivitis is 100% reversible. If not managed correctly, gingivitis can progress to the much more serious condition known as periodontal disease. Brushing, flossing and visiting your dentist are the most important steps you can take to avoid gingivitis.